[Note: Both parts of this FAQ have been combined into one file for this 
archive.]

Archive-name: www/faq/part1
Last-modified: 1995/26/1

                   WORLD WIDE WEB FREQUENTLY ASKED QUESTIONS

                      This is part 1 of a 2-part posting.
                   Part 2 begins with section 5 (providing
               information to the web). It should be the next
                           posting in this thread.
   


   This document resides on the World Wide Web on Sunsite (URL is
   http://sunsite.unc.edu/boutell/faq/www_faq.html ).
   
   If you are unfamiliar with the term "URL", read on and learn!
   
   Last update: 1/26/95 
   
Contents

     * 1: Recent changes to the FAQ
     * 2: Information about this document
     * 3: Elementary Questions
          + 3.1: What are WWW, hypertext and hypermedia?
          + 3.2: What is a URL?
          + 3.3: What are SGML and HTML?
          + 3.4: How does WWW compare to gopher and WAIS?
          + 3.5: Are there books about the web?
     * 4: Accessing the Web (User Questions)
          + 4.1: Introduction: How can I access the web? (Even by email!)
          + 4.2: Browsers Accessible by Telnet
          + 4.3: Obtaining browsers
               o 4.3.1: MS Windows, IBM OS/2 and MS Windows NT browsers
               o 4.3.2: MSDOS browsers
               o 4.3.3: Macintosh browsers
               o 4.3.4: Amiga browsers
               o 4.3.5: NeXTStep browsers
               o 4.3.6: X/DecWindows (graphical UNIX, VMS) browsers
               o 4.3.7: Text-based Unix and VMS browsers
               o 4.3.8: VM/CMS browsers
               o 4.3.9: Batch-mode "browsers"
          + 4.4: How can I access the web through a firewall?
          + 4.5: What is on the web?
               o 4.5.1: How do I find out what's new on the web?
               o 4.5.2: Where is the subject catalog of the web?
               o 4.5.3: How can I search through ALL web sites?
          + 4.6: How can I save an inline image to disk?
          + 4.7: How can I get sound from the PC speaker with WinMosaic?
          + 4.8: I have a Windows PC (or a Macintosh). Why can't I open
            WAIS URLs?
          + 4.9: I'm running XMosaic. Why can't I get external viewers
            working?
          + 4.10: Hey, I know, I'll write a WWW-exploring robot! Why not?
          + 4.11: How do I send newsgroup posts in HTML to my web client?
          + 4.12: I can't get SLIP. I want Mosaic. Is there a way? (YES!)
     * 5: Providing Information to the Web (Provider Questions)
          + 5.1: How can I provide information to the web?
          + 5.2: Obtaining Servers
               o 5.2.1: Unix Servers
               o 5.2.2: Macintosh Servers
               o 5.2.3: MS Windows, IBM OS/2 and MS Windows NT Servers
               o 5.2.4: MSDOS and Novell Netware Servers
               o 5.2.5: VMS Servers
               o 5.2.6: Amiga Servers
               o 5.2.7: VM/CMS Servers
               o 5.2.8: Yeah, but which is best?
          + 5.3: Producing HTML documents
               o 5.3.1: Writing HTML directly
               o 5.3.2: HTML editors
               o 5.3.3: Converting other formats to HTML
               o 5.3.4: Checking your HTML for errors
          + 5.4: How do I publicize my work?
          + 5.5: Can I buy space on an existing server?
          + 5.6: How fast does my net connection have to be?
          + 5.7: Advanced Provider Questions
               o 5.7.1: How do I set up a clickable image map?
               o 5.7.2: How do I make a "link" that doesn't load a new
                 page?
               o 5.7.3: Where can I learn how to create fill-out forms?
                    # 5.7.3.1: How can I create hidden fields in forms
                      (keeping state)?
                    # 5.7.3.2: How can users email me through their
                      browsers?
               o 5.7.4: How do I comment an HTML document?
               o 5.7.5: How can I create decent-looking tables and stop
                 using <PRE>...</PRE>?
               o 5.7.6: What is HTML Level 3 and where can I learn more
                 about it?
               o 5.7.7: How can I make interlaced and transparent GIFs?
                 And what are they?
               o 5.7.8: How come mailto: URLs don't work?
               o 5.7.9: How can I restrict and control access to my
                 server?
               o 5.7.10: Which format is better for WWW images, JPEG or
                 GIF?
               o 5.7.11: How can I mirror part of another server?
               o 5.7.12: How can I keep robots off my server?
               o 5.7.13: How can I keep statistics about my web site?
               o 5.7.14: How can I generate web pages on the fly from a
                 program?
                    # 5.7.14.1: How can I generate GIF images on the fly
                      from my CGI programs?
     * 6: Where can I discuss the Web?
          + 6.1: USENET Newsgroups
          + 6.2: Mailing Lists
     * 7: I want to know more.
     * 8: Credits
       
                  1: RECENT ADDITIONS AND CHANGES TO THE FAQ
                                       
     * Added htmlchek to validation section
     * Added information on interlaced GIFs
     * Added information on the WN Server
     * Added information on CGI script authoring
     * Added information on the gd GIF-generating library
     * Updated email links section
     * More books!
     * Slipknot section updated
     * GLACI-HTTPD, a WWW server for Novell Netware
     * WWW mailing lists section
     * Updated URL for Gabriel White's HTML editor reviews
     * IBM OS/2 WebExplorer
     * MapMaker: From xv's Visual Schnauzer to an imagemap
     * Added comp.infosystems.www.announce
     * Added the Arena browser
       
   
   
                      2: INFORMATION ABOUT THIS DOCUMENT
                                       
   This is an introduction to the World Wide Web project, describing the
   concepts, software and access methods. It is aimed at people who know
   a little about navigating the Internet, but want to know more about
   WWW specifically. If you don't think you are up to this level, try an
   introductory Internet book such as Ed Krol's "The Whole Internet" or
   "EFF's Guide to the Internet". The latter is available electronically
   by anonymous FTP from ftp.eff.org in the directory
   pub/Net_info/EFF_Net_Guide.
   
   This informational document is posted to news.answers,
   comp.infosystems.www.users, comp.infosystems.www.providers,
   comp.infosystems.www.announce, comp.infosystems.www.misc,
   comp.infosystems.gopher, comp.infosystems.wais and alt.hypertext every
   four days (please allow a day or two for it to propagate to your
   site). The latest and best version is always available on the web as
   http://sunsite.unc.edu/boutell/faq/www_faq.html , and is mirrored in
   Japan (URL is
   http://www.glocom.ac.jp/mirror/sunsite.unc.edu/boutell/faq/www_faq.htm
   l ). (see section 3.2, "What is a URL?" to understand what this term
   means.) If you run a mirror site which automatically mirrors this
   document, please submit the URL for inclusion in the list of mirrors.
   Thanks to both Sunsite and Glocom.
   
   This document is also available by anonymous FTP from ftp.netcom.com
   in the directory pub/bo/boutell/faq.
   
   In addition, the most recently posted version of this document is kept
   on the news.answers archive on rtfm.mit.edu in
   /pub/usenet/news.answers/www/faq. For information on FTP, send e-mail
   to mail-server@rtfm.mit.edu with:

send usenet/news.answers/finding-sources

   in the body (not subject line) of your message, instead of asking me.
   
   
   
   If you want the HTML version but are located behind a firewall, you
   can acquire it from CERN's WWW email server. Send mail to
   listproc@www0.cern.ch with the following single line in the body
   (leave the subject blank):
   
   source http://sunsite.unc.edu/boutell/faq/www_faq.html
   
   Thomas Boutell maintains this document. Feedback about it is to be
   sent via e-mail to boutell@netcom.com.
   
   In all cases, regard this document as out of date. Definitive
   information should be on the web, and static versions such as this
   should be considered unreliable at best. The most up-to-date version
   of the FAQ is the version maintained on the web. Please excuse any
   formatting inconsistencies in the posted version of this document, as
   it is automatically generated from the on-line version.
   
                            3: ELEMENTARY QUESTIONS
                                       
3.1: What are WWW, hypertext and hypermedia?

   WWW stands for "World Wide Web". The WWW project, started by CERN (the
   European Laboratory for Particle Physics), seeks to build a
   distributed hypermedia system.
   
   
   
   The advantage of hypertext is that in a hypertext document, if you
   want more information about a particular subject mentioned, you can
   usually "just click on it" to read further detail. In fact, documents
   can be and often are linked to other documents by completely different
   authors -- much like footnoting, but you can get the referenced
   document instantly!
   
   To access the web, you run a browser program. The browser reads
   documents, and can fetch documents from other sources. Information
   providers set up hypermedia servers which browsers can get documents
   from.
   
   The browsers can, in addition, access files by FTP, NNTP (the Internet
   news protocol), gopher and an ever-increasing range of other methods.
   On top of these, if the server has search capabilities, the browsers
   will permit searches of documents and databases.
   
   The documents that the browsers display are hypertext documents.
   Hypertext is text with pointers to other text. The browsers let you
   deal with the pointers in a transparent way -- select the pointer, and
   you are presented with the text that is pointed to.
   
   Hypermedia is a superset of hypertext -- it is any medium with
   pointers to other media. This means that browsers might not display a
   text file, but might display images or sound or animations.
   
3.2: What is a URL?

   URL stands for "Uniform Resource Locator". It is a draft standard for
   specifying an object on the Internet, such as a file or newsgroup.
   
   URLs look like this: (file: and ftp: URLs are synonymous.)
     * file://wuarchive.wustl.edu/mirrors/msdos/graphics/gifkit.zip
     * ftp://wuarchive.wustl.edu/mirrors
     * http://info.cern.ch:80/default.html
     * news:alt.hypertext
     * telnet://dra.com
       
   
   
   The first part of the URL, before the colon, specifies the access
   method. The part of the URL after the colon is interpreted specific to
   the access method. In general, two slashes after the colon indicate a
   machine name (machine:port is also valid).
   
   When you are told to "check out this URL", what to do next depends on
   your browser; please check the help for your particular browser. For
   the line-mode browser at CERN, which you will quite possibly use first
   via telnet, the command to try a URL is "GO URL" (substitute the
   actual URL of course). In Lynx you just select the "GO" link on the
   first page you see; in graphical browsers, there's usually an "Open
   URL" option in the menus.
   
3.3: What are SGML and HTML?

   Documents on the World Wide Web are written in a simple "markup
   language" called HTML, which stands for Hypertext Markup Language. See
   section 5.3 for more information about creating HTML documents for use
   on the web.
   
   SGML is a much broader language which is used to define particular
   markup languages for particular purposes. HTML is just a specific
   application of SGML. You can learn more about SGML, and the rationale
   behind HTML, by reading A Gentle Introduction to SGML (URL is
   http://etext.virginia.edu/bin/tei-tocs?div=DIV1%26id=SG ), a document
   provided by the Text Encoding Initiative. (Note: Some browsers
   apparently crash on this URL. There's nothing wrong with the document;
   try another browser if you have problems.)
   
3.4: How does WWW compare to gopher and WAIS?

   While all three of these information presentation systems are
   client-server based, they differ in terms of their model of data. In
   gopher, data is either a menu, a document, an index or a telnet
   connection. In WAIS, everything is an index and everything that is
   returned from the index is a document. In WWW, everything is a
   (possibly) hypertext document which may be searchable.
   
   In practice, this means that WWW can represent the gopher (a menu is a
   list of links, a gopher document is a hypertext document without
   links, searches are the same, telnet sessions are the same) and WAIS
   (a WAIS index is a searchable page, returning a document with no
   links) data models as well as providing extra functionality.
   
   World Wide Web usage grew far beyond Gopher usage in the last few
   months, according to the statistics-keepers of the Internet backbone.
   (Of course, World Wide Web browsers can also access Gopher servers,
   which inflates the numbers for the latter.) WWW has long since reached
   critical mass, with new commercial and noncommercial sites appearing
   daily.
   
3.5: Are there books about the web?

   
   
   Yes, quite a few. A brief list follows. New entries are solicited.
   Please include ISBN numbers and/or ordering information.
   
   The Mosaic Handbook (Mac, Windows and X editions)
          From O'Reilly. A short, sweet guide to the World Wide Web from
          a Mosaic user's perspective. Mac and Windows versions Include
          Enhanced NCSA Mosaic on floppy disk; the X Window System
          version includes NCSA Mosaic on CD-ROM. Telnet or gopher to
          gopher.ora.com (log in as gopher) or find details on the web
          (URL is http://gnn.com/ora/ ). Wherever fine X Window System
          books and Nutshell Guides are sold.
          
   The World Wide Web Unleashed
          From Sams Publishing. By John December and Neil Randall.
          Additional chapters contributed by others; I wrote the chapter
          on HTML editors and filters. Covers both user and provider
          issues in detail. Supporting pages available on the web (URL is
          http://www.rpi.edu/~decemj/works/wwwu.html ). 1057 pages. ISBN:
          0-672-30617-4. Call 1-800-428-5331 or +1-317-581-3500 for
          ordering information.
          
   Spinning the Web: How to Provide Information on the Internet
          From Van Nostrand Reinhold. By Andrew Ford. Oriented toward
          those with an interest in putting their data on the web. ISBN:
          1-850-32141-8 (New York), 0-442-01962-9 (London). Available in
          December 1994.
          
   Teach Yourself Web Publishing with HTML in a Week
          From Sams Publishing. By Laura Lemay. Also oriented toward
          those who plan to publish materials on the web. ISBN:
          0-672-30667-0. 400 pages. Includes information on setting up
          servers and handling forms results as well as HTML writing and
          editing. (URL is: http://slack.lne.com/lemay/theBook/index.html
          ) Available December 22nd, 1994. Call 1-800-428-5331 or
          +1-317-581-3500 for ordering information.
          
   The HTML Manual of Style
          From Ziff-Davis Press. By Larry Aronson. Chapters: introduction
          to the WWW, the HTML language, writing HTML documents, and HTML
          examples. 120 pages. Available in December 1994.
          
   The Internet via Mosaic and World-Wide Web
          From Ziff-Davis Press. By Steve Browne. Details on obtaining
          Mosaic and Trumpet Winsock, getting it all set up, and what to
          do with it once it works. A chapter of interesting sites on the
          Web as well. ISBN: 1-56276-259-1.
          
   MOSAIC Quick Tour
          From Ventana Press. By Gareth Branwyn. A good guide to
          installing and using NCSA Mosaic under Windows. Includes basic
          HTML and trouble-shooting chapters. "More hand-holding than the
          FAQ and gives lots of details." - Mari J. Stoddard
          
   Managing Internet Information Services
          From O'Reilly and Associates. By Cricket Liu, Jerry Peek, Russ
          Jones, Bryan Buus & Adrian Nye. A good choice for those who
          will be installing and maintaining WWW servers; also includes
          documentation on HTML, imagemaps and the like. Also covers
          other types of Internet services.
          
   Hands-On Mosaic: A Guide for Window Users
          From Prentice Hall. By Dr. David Sachs & Henry Stair. ISBN:
          0-13-172321-9.
          
   HTML Authoring for Fun & Profit
          From Prentice Hall. By Mary Morris. Jan 1995. ISBN:
          0-13-359290-1.
          
   NCSA Mosaic Handbook
          From Prentice Hall. By Amy K. Kreiling & Frank Baker. Jan 1995.
          ISBN: 0-13-196692-8.
          
   Plug-n-Play Mosaic for Windows
          From Sams. By Angela Gunn. ISBN 0-672-30627-1. 300 pages. Disks
          include a special version of Enhanced NCSA Mosaic for Windows
          with built-in TCP/IP Winsock and dialer, and an automated
          configuration program (hence "plug-n-play"). The book is an
          introduction to Mosaic and the Web with some coverage of
          creating a home page and HTML and, of course, the obligatory
          directory of Web sites.
          
   Using Mosaic
          From Que. Ed. by Que Development Group. ISBN: 0-7897-0021-2.
          Covers NCSA Mosaic for Windows and the Macintosh.
          
   Using the World Wide Web
          From Que. Ed. by Que Development Group. ISBN: 0-7897-0016-6.
          
   Mosaic User's Guide
          From MIS Press. By Bryan Pfaffenberger. ISBN: 1-55828-409-5.
          
   Using Mosaic for Windows
          From Electric Avenue Press. By Stephen Gauer. ISBN:
          0-969-8853-0-X.
          
   
   
4.1: Introduction: how can I access the web?

   You have three options: use a browser on your own machine (the best
   option), use a browser that can be telnetted to (not as good), or
   access the web by email (the least attractive, but for some it's the
   only way). It is always best to run a browser on your own machine,
   unless you absolutely cannot do so; but feel free to telnet to a
   browser for your first look at the web, or use email if the telnet
   command does not work on your system (try it first!). Note that
   "your machine" can be defined as a system you dial into from home,
   such as netcom or another account provider. Running a text-based
   browser on such a system is still preferable to telnetting to a
   faraway site.
   
   The following sections cover telnetting to a browser and obtaining
   your own browser; if neither of these are possible for you (because
   you have only an email-and-news connection to the Internet), here is
   how to access a web page by email:
   
   Send email to server@mail.w3.org (preferred) or to
   listserv@info.cern.ch (older address if the first fails) containing
   the following single line. (What you put on the subject line doesn't
   matter; blank is OK. This line should go in the text of the message.)
   You will receive as a reply a simple page intended to help you learn
   more about the Web.

send http://www.earn.net/gnrt/www.html

   
   
4.2: Browsers accessible by telnet

   An up-to-date list of these is available on the Web as
   http://info.cern.ch/hypertext/WWW/FAQ/Bootstrap.html and should be
   regarded as an authoritative list.
   
   telnet.w3.org
          A telnettable browser provided by the W3 coalition.
          
   www.cc.ukans.edu
           Offers Lynx, a full screen browser which requires a vt100
          terminal. Log in as www. Does not allow users to "go" to
          arbitrary URLs, so GET YOUR OWN COPY of Lynx and install it on
          your system if your administrator has not done so already. The
          best plain-text browser, so move mountains if necessary to get
          your own copy of Lynx!
          
   www.njit.edu
          (or telnet 128.235.163.2) Log in as www. A full-screen browser
          in New Jersey Institute of Technology. USA.
          
   www.huji.ac.il
          A dual-language Hebrew/English database, with links to the rest
          of the world. The line mode browser, plus extra features. Log
          in as www. Hebrew University of Jerusalem, Israel.
          
   sun.uakom.cs
          Slovakia. Has a slow link, only use from nearby.
          
   info.funet.fi
          (or telnet 128.214.6.102). Log in as www. Offers several
          browsers, including Lynx (goto option is disabled there also).
          
   fserv.kfki.hu
          Hungary. Has slow link, use from nearby. Login is as www.
          
4.3: Obtaining browsers

   The preferred method of access of the Web is to run a browser
   yourself. Browsers are available for many platforms, both in source
   and executable forms. Here is a list generated from the authoritative
   list, http://info.cern.ch/hypertext/WWW/Clients.html .
   
  4.3.1: MICROSOFT WINDOWS BROWSERS
  
   
   
   NOTE: Most of these browsers require that you have SLIP, PPP or other
   TCP/IP networking on your PC. The sole exception is SlipKnot, which
   has limited features but operates well without a proper Internet
   connection. SLIP or PPP can be accomplished over phone lines. You can
   do this one of two ways: using a proper SLIP account, which requires
   the active cooperation of your network provider or educational
   institution, or using The Internet Adapter (section 4.12), a product
   which simulates SLIP through your dialup Unix shell account. If you
   only have non-Unix based dialup shell access, or have no PC at home,
   your best option at this time is to run Lynx on the VMS (or Unix,
   or...) system you call, or telnet to a browser if you cannot do so.
   
   Cello  Browser from Cornell LII. Available by anonymous FTP from
          ftp.law.cornell.edu in the directory /pub/LII/cello.
          
   Mosaic for Windows
          From NCSA. Available by anonymous FTP from ftp.ncsa.uiuc.edu in
          the directory PC/Windows/Mosaic.
          
   WinWeb
          From EINet. Available by anonymous FTP from ftp.einet.net in
          the directory /einet/pc/winweb as the file winweb.zip.
          
   Netscape
          From Mosaic Communications Corp (URL is:
          http://home.mcom.com/info/index.html ). Downloads and displays
          images incrementally while you read pages, which also display
          incrementally, making it the best browser at the time of this
          writing for those who connect to the web via modems. Also
          supports many extensions to HTML, although not all conform to
          the proposed standard. Netscape is a commercial product but can
          be evaluated free of charge for an unlimited period of time by
          individuals. Netscape supports some of the official extended
          HTML tags as well as its own variations. The 16-bit version
          works under both OS/2 and Windows. Available by anonymous FTP
          from the following sites (use the mirror closest to you; see
          the URL above for the latest list):
          
          + ftp://ftp.mcom.com/netscape/
          + ftp://ftp.uu.net/networking/info-service/www/mcc/
          + ftp://ftp.digital.com/pub/net/infosys/Netscape/
          + ftp://ftp.icsi.net/pub/packages/netscape/
          + ftp://www.sandia.gov/Netscape/
          + ftp://lark.cc.ukans.edu/Netscape/
          + ftp://www.jsc.nasa.gov/pub/netscape/
          + ftp://ftp.meer.net/pub/Netscape/
          + ftp://src.doc.ic.ac.uk/packages/Netscape/
            
   Spry Mosaic
          From Spry. Available by anonymous FTP from ftp.spry.com in the
          directory AirMosaicDemo as the file AMOSDEMO.EXE. Spry Mosaic
          is a commercial product but a demonstration version is
          available and can be registered inexpensively. Works under
          Windows and OS/2. Supports the mailto: URL, transparent GIFs,
          ALT tags, hierarchical hotlists, etc.
          
   Booklink
          From Booklink. Available by anonymous FTP from ftp.booklink.com
          in the directory lite; this is a demonstration version of the
          full browser, which costs $99. Booklink can open many
          simultaneous connections in different windows and display
          images and pages progressively; at the time of this writing it
          is the only browser to equal Netscape in this area. The "lite"
          version can only open two simultaneous connections, however.
          
   SlipKnot
          SlipKnot is the only graphical WWW browser that operates
          entirely without SLIP, PPP, an Ethernet connection, or special
          server-side software (but consider TIA, section 4.12 for
          another workaround). SlipKnot supports multiple fonts, inline
          images, and review of documents you have already received while
          new documents arrive, and it operates entirely through your
          regular Unix shell account. SlipKnot does not require that
          you install any new software on your Unix shell account.
          (However, it is lacking certain important features as a result,
          such as forms and validation; this will keep you from accessing
          some web pages. SlipKnot does support the <ISINDEX> tag, which
          many sites support as a simpler alternative to forms.) You can
          obtain SlipKnot by anonymous FTP from ftp.netcom.com in the
          directory pub/pbrooks/slipknot or from oak.oakland.edu in the
          directory SimTel/win3/internet. For more information, see the
          SlipKnot information page (URL is
          http://www.interport.net/slipknot/slipknot.html ) or send a
          blank email message to slipknot@micromind.com.
          
   IBM OS/2 WebExplorer
          A native IBM OS/2 web browser. WebExplorer is a multithreaded
          application and replaces the usual "back" and "forward" buttons
          with a visual map of your exploration of the web. IBM
          WebExplorer can be acquired by anonymous FTP from
          ftp01.ny.us.ibm.net in the directory pub/WebExplorer/ .
          
   
   
  4.3.2: MSDOS BROWSERS
  
   
   
   NOTE: These browsers require that you have SLIP, PPP or other TCP/IP
   networking on your PC. SLIP or PPP can be accomplished over phone
   lines. You can do this one of two ways: using a proper SLIP account,
   which requires the active cooperation of your network provider or
   educational institution, or using The Internet Adapter (section 4.12),
   a product which simulates SLIP through your dialup Unix shell account.
   If you only have non-Unix based dialup shell access, or have no PC at
   home, your best option at this time is to run Lynx on the VMS (or
   Unix, or...) system you call, or telnet to a browser if you cannot do
   so.
   
   DosLynx
          DosLynx is an excellent text-based browser for use on DOS
          systems. You must have a level 1 packet driver, or an emulation
          thereof, or you will only be able to browse local files;
          essentially, if your PC has an Ethernet connection, or you have
          SLIP, you should be able to use it. DosLynx can view GIF
          images, but not when they are inline images (as of this
          writing). See the README.HTM file at the DosLynx site for
          details. You can obtain DosLynx by anonymous FTP from
          ftp2.cc.ukans.edu in the directory pub/WWW/DosLynx; the URL is
          ftp://ftp2.cc.ukans.edu/pub/WWW/DosLynx/.
          
  4.3.3: MACINTOSH BROWSERS
  
   
   
   NOTE: These browsers require that you have SLIP, PPP or other TCP/IP
   networking on your PC. SLIP or PPP can be accomplished over phone
   lines. You can do this one of two ways: using a proper SLIP account,
   which requires the active cooperation of your network provider or
   educational institution, or using The Internet Adapter (section 4.12),
   a product which simulates SLIP through your dialup Unix shell account.
   If you only have non-Unix based dialup shell access, or have no PC at
   home, your best option at this time is to run Lynx on the VMS (or
   Unix, or...) system you call, or telnet to a browser if you cannot do
   so.
   
   Mosaic for Macintosh
          From NCSA. Full featured. Available by anonymous FTP from
          ftp.ncsa.uiuc.edu in the directory Mac/Mosaic.
          
   Netscape
          From Mosaic Communications Corp (URL is:
          http://home.mcom.com/info/index.html ). Downloads and displays
          images incrementally while you read pages, which also display
          incrementally, making it the best browser at the time of this
          writing for those who connect to the web via modems. Also
          supports many extensions to HTML, although not all conform to
          the proposed standard. Netscape is a commercial product but is
          free for personal use by individuals. Version 0.9 (available to
          the public as of this writing) does not support printing, but
          this is promised in the forthcoming version 1.0. Contrary to
          popular myth, version 1.0 will be free for personal use, just
          like version 0.9. Available by anonymous FTP from the
          following sites (use the mirror closest to you; see the URL
          above for the latest list):
          
          + ftp://ftp.mcom.com/netscape/
          + ftp://ftp.uu.net/networking/info-service/www/mcc/
          + ftp://ftp.digital.com/pub/net/infosys/Mosaic_Comm/Netscape/
          + ftp://ftp.icsi.net/pub/packages/netscape/
          + ftp://www.sandia.gov/Netscape/
          + ftp://lark.cc.ukans.edu/Netscape/
          + ftp://www.jsc.nasa.gov/pub/netscape/
          + ftp://ftp.meer.net/pub/Netscape/
          + ftp://src.doc.ic.ac.uk/packages/Netscape/
            
   Samba  From CERN. Basic. Available by anonymous FTP from info.cern.ch
          in the directory /ftp/pub/www/bin as the file mac.
          
   MacWeb
          From EINet. Has features that Mosaic lacks; lacks some features
          that Mosaic has. Available by anonymous FTP from ftp.einet.net
          in the directory einet/mac/macweb.
          
   
   
  4.3.4: AMIGA BROWSERS
  
   AMosaic
          Browser for AmigaOS, based on NCSA's Mosaic. Supports older
          Amigas as well as the newer machines in the latest versions;
          available for anonymous ftp from max.physics.sunysb.edu in the
          directory /pub/amosaic, or from aminet sites in
          /pub/aminet/comm/net. see the site for details. See the URL
          http://insti.physics.sunysb.edu/AMosaic/home.html .
          
   Emacs-W3
          The Emacs-W3 browser works under Gnu Emacs on the Amiga (see
          section 4.3.7).
          
  4.3.5: NEXTSTEP BROWSERS
  
   
   
   Note: NeXTStep systems can also run X-based browsers using one of the
   widely used X server products for the NeXT. The browsers listed here,
   by contrast, are native NeXTStep applications.
   
   SpiderWoman
          A brand-new (as of 12/94), multithreaded, graphical browser for
          NeXTStep. Available by anonymous FTP from sente.epfl.ch in the
          directory pub/software.
          
   OmniWeb
          A World Wide Web browser for NeXTStep. The URL for more
          information is http://www.omnigroup.com/; you can ftp the
          package from ftp.omnigroup.com in the /pub/software/ directory.
          
   WorldWideWeb, CERN's NeXT Browser-Editor
          A browser/editor for NeXTStep. Currently out of date; editor
          not operational. Allows wysiwyg hypertext editing. Requires
          NeXTStep 3.0. Available for anonymous FTP from info.cern.ch in
          the directory /pub/www/src.
          
  4.3.6: X/DECWINDOWS (GRAPHICAL UNIX, VMS) BROWSERS
  
   NCSA Mosaic for X
          Unix browser using X11/Motif. The original multimedia browser.
          Full http 1.0 support including PUT-method forms, image maps,
          etc. Recent beta versions have limited support for tables.
          Available by anonymous FTP from ftp.ncsa.uiuc.edu in the
          directory Mosaic.
          
   NCSA Mosaic for VMS
          Browser using X11/DecWindows/Motif. For the VMS operating
          system. Full http 1.0 support including PUT-method forms, image
          maps, etc. Probably the best browser available for VMS.
          Available by anonymous FTP from ftp.ncsa.uiuc.edu in the
          directory Mosaic.
          
   Netscape
          From Mosaic Communications Corp (URL is:
          http://home.mcom.com/info/index.html ). Downloads and displays
          images incrementally while you read pages, which also display
          incrementally, making it the best browser at the time of this
          writing for those who connect to the web via modems. Also
          supports many extensions to HTML, although not all conform to
          the proposed standard. Netscape is a commercial product but is
          free for personal use by individuals. Version 0.9 (available to
          the public as of this writing) does not support printing, but
          this is promised in the forthcoming version 1.0. Contrary to
          popular myth, version 1.0 will be free for personal use, just
          like version 0.9. Available by anonymous FTP from the
          following sites (use the mirror closest to you; see the URL
          above for the latest list):
          
          + ftp://ftp.mcom.com/netscape/
          + ftp://ftp.uu.net/networking/info-service/www/mcc/
          + ftp://ftp.digital.com/pub/net/infosys/Mosaic_Comm/Netscape/
          + ftp://ftp.icsi.net/pub/packages/netscape/
          + ftp://www.sandia.gov/Netscape/
          + ftp://lark.cc.ukans.edu/Netscape/
          + ftp://www.jsc.nasa.gov/pub/netscape/
          + ftp://ftp.meer.net/pub/Netscape/
          + ftp://src.doc.ic.ac.uk/packages/Netscape/
            
   Quadralay GWHIS Viewer (Commercial Mosaic)
          Quadralay offers a commercial-grade (not free!) version of
          Mosaic for Unix systems, with Windows and Macintosh versions
          expected in the future. (URL is:
          http://www.quadralay.com/products/products.html#gwhis )
          
   tkWWW Browser/Editor for X11
          Unix Browser/Editor for X11. (Beta test version.) Available for
          anonymous ftp from harbor.ecn.purdue.edu in the directory
          tkwww[extension] (followed by an extension possibly dependent
          on the current version). Please ftp to the site and look for
          the latest version (or use the link above). Supports WSYIWYG
          HTML editing.
          
   MidasWWW Browser
          A Unix/X browser from Tony Johnson. (Beta, works well.)
          
   Viola for X (Beta)
          Viola has two versions for Unix/X: one using Motif, one using
          Xlib (no Motif). Handles HTML Level 3 forms and tables. Has
          extensions for multiple columning, collapsible/expandable list,
          client-side document include. Available by anonymous FTP from
          ora.com in /pub/www/viola. More information available at the
          URL http://xcf.berkeley.edu/ht/projects/viola/README.
          
   Chimera
          Unix/X Browser using Athena (doesn't require Motif). Supports
          forms, inline images, etc.; closest to Mosaic in feel of the
          non-Motif X11 browsers. Available for anonymous FTP from
          ftp.cs.unlv.edu in the directory /pub/chimera.
          
   Emacs w3 mode
          The Emacs w3 mode supports multiple fonts, color, inline
          images, movies, and the whole nine yards when run under a
          graphical version of emacs; see section 4.3.7.
          
   Arena  Arena's primary purpose is to be a testbed for HTML Level 3
          documents. As a result, Arena supports many of the new and
          interesting features of HTML Level 3. As of this writing it is
          still in prerelease and expectations should be set accordingly!
          Available by anonymous FTP from ftp.w3.org in the directory
          pub/www/arena/ .
          
    4.3.7: Text-mode Unix and VMS browsers
    
   
   
   These are text-based browsers for Unix (and in some cases also VMS)
   systems. In many cases your system administrator will have already
   installed one or more of these packages; check before compiling your
   own copy.
   
   Line Mode Browser
          This program gives W3 readership to anyone with a dumb
          terminal. A general purpose information retrieval tool.
          Available by anonymous ftp from info.cern.ch in the directory
          /pub/www/src.
          
   The "Lynx" full screen browser
          This is a hypertext browser for vt100s using full screen, arrow
          keys, highlighting, etc. Available by anonymous FTP from
          ftp2.cc.ukans.edu.
          
   Tom Fine's perlWWW
          A tty-based browser written in perl. Available by anonymous FTP
          from archive.cis.ohio-state.edu in the directory pub/w3browser
          as the file w3browser-0.1.shar.
          
   For VMS
          Dudu Rashty's full screen client based on VMS's SMG screen
          management routines. Available by anonymous FTP from
          vms.huji.ac.il in the directory www/www_client.
          
   Emacs w3-mode
          A WWW browser for emacs. Runs under Xwindows, NeXTstep, VMS,
          OS/2, Windows NT, Windows 3.1, AmigaDOS, or just about any Unix
          system. Also has fonts, color, inline images, and mouse support
          if using Lemacs, Epoch, or Emacs 19. Also works in local mode
          under DOS and on the Macintosh. Available by anonymous ftp from
          ftp.cs.indiana.edu in the directory pub/elisp/w3.
          
   
   
  4.3.8: VM/CMS BROWSERS
  
   Albert
          A WWW browser for the VM/CMS operating system. Available by
          anonymous FTP from gopher.ufl.edu in the directory pub/vm/www/.
          
   
   
  4.3.9: BATCH-MODE "BROWSERS"
  
   Batch mode browser
          A batch-mode "browser", url_get, which is available through the
          URL http://www.utexas.edu/~zippy/url_get.html . It can be
          retrieved via anonymous FTP to ftp.cc.utexas.edu, as the file
          /pub/zippy/url_get.tar.Z. This package is intended for use in
          cron jobs and other settings in which fetching a page in a
          command-line fashion is useful.
          
4.4: How can I access the web through a firewall?

   A "proxy server" is a specialized HTTP server which (typically) runs
   on a firewall machine, providing access to the outside world for
   people inside the firewall. The CERN httpd can be configured to run as
   a proxy. Furthermore, it is able to perform caching of documents,
   resulting in faster response times.
   
   
   
   If you cannot arrange to run a proxy server (definitely the
   recommended approach), read on:
   
   For information on using NCSA Mosaic from behind a firewall, please
   read the following. In general, browsers can be made useful behind
   firewalls through the use of a package called "SOCKS"; the source must
   be modified slightly and rebuilt to accommodate this. Whenever
   possible, work with your network administrators to solve the
   problem, not against them.
   
   An excerpt from the NCSA Mosaic FAQ:
   
   NCSA Mosaic requires a direct internet connection to work, but some
   folks have put together a package that works behind firewalls. This is
   completely unsupported by NCSA, but here is the latest announcement:
   
     November 15, 1993: C&C Software Technology Center (CSTC) of NEC
     Systems Lab has made available a version of SOCKS, a package for
     running Internet clients from behind firewalls without breaching
     security requirements, that includes a suitably modified version of
     Mosaic for X 2.0. Beware: such a version is not supported by NCSA;
     we can't help with questions or problems arising from the
     modifications made by others. But, we encourage you to check it
     out if it's interesting to you. Questions and problem notifications
     can be sent to Ying-Da Lee (ylee@syl.dl.nec.com).
     
   
   
4.5: What is on the web?

   Currently accessible through the web:
     * anything served through gopher
     * anything served through WAIS
     * anything on an FTP site
     * anything on Usenet
     * anything accessible through telnet
     * anything in hytelnet
     * anything in hyper-g
     * anything in techinfo
     * anything in texinfo
     * anything in the form of man pages
     * sundry hypertext documents
       
   
   
  4.5.1: HOW DO I FIND OUT WHAT'S NEW ON THE WEB?
  
   comp.infosystems.www.announce
          The newsgroup comp.infosystems.www.announce carries
          announcements of new resources on the World Wide Web. Since
          newsgroups are distributed, it can be accessed reliably even
          when the net is very busy.
          
   What's New With NCSA Mosaic
          The unofficial newspaper of the World Wide Web is What's New
          With NCSA Mosaic (URL is
          http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html )
          , which carries announcements of new servers on the web and
          also of new web-related tools. This should be in your hot list
          if you're not using Mosaic (which can access it directly
          through the help menu).
          
   comp.internet.net-happinings
          You can also check out the newsgroup
          comp.internet.net-happenings, which carries WWW announcements
          and many other Internet-related announcements.
          
   
   
  4.5.2: WHERE IS THE SUBJECT CATALOG OF THE WEB?
  
   There are several. There is no mechanism inherent in the web which
   forces the creation of a single catalog (although there is work
   underway on automatic mechanisms to catalog web sites). The best-known
   catalog, and the first, is The WWW Virtual Library (URL is
   http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html ),
   maintained by CERN. The Virtual Library is a good place to find
   resources on a particular subject, and has separate maintainers for
   many subject areas.
   
   There is also a newer cataloging system called ALIWEB that requires
   very little effort to maintain and is growing rapidly (URL is
   http://web.nexor.co.uk/aliweb/doc/aliweb.html ).
   
  4.5.3: HOW CAN I SEARCH THROUGH ALL WEB SITES?
  
   Several people have written robots which create indexes of web sites
   -- including sites which have not arranged to be mentioned in the
   newspapers and catalogs above. (Before writing your own robot, please
   read the section on robots.)
   
   Here are a few such automatic indexes you can search:
     * WebCrawler (URL is
       http://webcrawler.cs.washington.edu/WebCrawler/WebQuery.html )
       builds an impressively complete index; on the other hand, since it
       indexes the content of documents, it may find many links that
       aren't exactly what you had in mind. However, it does a good job
       of sorting the documents it finds according to how closely they
       match your search.
     * World Wide Web Worm (URL is
       http://www.cs.colorado.edu/home/mcbryan/WWWW.html ) builds its
       index based on page titles and URL contents only. This is somewhat
       less inclusive, but pages it finds are more likely to be an exact
       match with your needs.
     * Lycos (URL is http://fuzine.mt.cs.cmu.edu/mlm/lycos-home.html ) is
       another web-indexing robot, which includes the ability to submit
       the URLs of your own documents by hand, ensuring that they are
       available for searching.
       
   You can read about other robots in the robots section.
   
4.6: How can I save an inline image to disk?

   
   
   Here are two ways:
   
   1. Turn on "load to local disk" in your browser, if it has such an
   option; then reload images. You'll be prompted for filenames instead
   of seeing them on the screen. Be sure to shut it off when you're done
   with it.
   
   2. Choose "view source" and browse through the HTML source; find the
   URL for the inline image of interest to you; copy and paste it into
   the "Open URL" window. This should load it into your image viewer
   instead, where you can save it and otherwise muck about with it.
   
4.7: How can I get sound from the PC speaker with WinMosaic?

   
   
   This piece of wisdom donated by Hunter Monroe:
   
   This section explains how to install sound on a PC which already has a
   working version of Mosaic for Microsoft Windows. Be warned in advance
   that the results may be poor.
   
   To get Mosaic to produce sound out of the PC speaker, first, you need
   a driver for the speaker. You can get the Microsoft speaker driver
   from the URL ftp://ftp.microsoft.com/Softlib/MSLFILES/SPEAK.EXE or by
   doing an Archie search to find it somewhere else. SPEAK.EXE is a
   self-extracting file. Copy the speak.exe file to a new directory, and
   then type "SPEAK" at the DOS prompt. Do not put the file SPEAKER.DRV
   in a separate directory from OEMSETUP.INF.
   
   Now, you need to install the driver. In Windows, from the Program
   Manager choose successively Main/Control Panel/Drivers/Add/Unlisted or
   updated drivers/(enter path of SPEAK.EXE)/PC Speaker. At this point
   some strange sounds come out as the driver is initialized. Change the
   settings to improve the sound quality on the various sounds: tada,
   chimes, etc. Click OK when you are finished and choose the Restart
   windows option.
   
   Having installed the speaker driver, you will now get sounds whenever
   you start Windows, make a mistake, or exit Windows. If you do not want
   this, from the Main/Control Panel/Sounds menu, make sure there is no X
   next to "Enable System Sounds."
   
   Now, you need a sound viewer program that Mosaic can call to display
   sounds. NCSA unfortunately recommend WHAM, which does not work well
   with a PC speaker. Get the program WPLANY instead. You can find a copy
   nearby with an Archie search on the string "wplny"; the current
   version is WPLNY09B.ZIP. For details on archie and other basic issues
   related to FTP, please read the Usenet newsgroup
   news.announce.newusers.
   
   Move the zip file to a new directory, and use an unzip program like
   pkunzip to unzip it, producing the files WPLANY.EXE and WPLANY.DOC.
   Then edit the MOSAIC.INI file to remove the "REM" before the line
   "TYPE9=audio/basic". Then, you need lines in the section below that
   read something like: audio/basic="c:\wplany\wplany.exe %ls"
   audio/wav="c:\wplany\wplany.exe %ls" where you have filled in the
   correct path for wplany.exe. The MOSAIC.INI file delivered with Mosaic
   may have NOTEPAD.EXE on the audio/basic line, but this will not work.
   Now, restart Mosaic, and you should now be able to produce sounds. To
   check this, with Mosaic choose File/Local File/\WINDOWS\*.WAV and then
   try to play TADA.WAV. Then, you might try the Mosaic Demo document for
   some .AU sounds, but you are lucky if your speaker produces something
   you can understand.
   
4.8: I have a Windows PC or Macintosh. Why can't I access WAIS URLs?

   
   
   This answer provided by Michael Grady (m-grady@uiuc.edu):
   
   The version of Mosaic for X has "wais client" code built-in to it.
   This was relatively easy for the developers to do, because there was
   already a set of library routines for talking to WAIS available for
   Unix as "public domain" (freeWAIS). I don't think there is such a
   library of routines for PC/Windows or Mac, which would make it much
   more difficult for the Mosaic versions for Windows and the Mac to add
   "wais client" capability. Therefore, at least for now, neither the
   Windows or Mac versions of Mosaic support direct query of a WAIS
   server (i.e. can act as wais clients themselves).
   
4.9: I'm running XMosaic. Why can't I get external viewers working...

   ... No matter what no matter what I do to my .mailcap and .mime.types
   files?
   
   Answer provided by Ronald E. Daniel (rdaniel@acl.lanl.gov):
   
     
     
     Mosaic only looks at the .mime.types file if it has no idea what the
     document's type is. This is actually a very rare situation.
     Essentially all servers now use the HTTP/1.0 protocol, which means
     that they tell Mosaic (or other browsers) what the document's MIME
     Content-type is. The servers use a file very much like Mosaic's
     .mime.types file to infer the Content-type from the filename's
     extension.
     
     It is pretty simple to find out if this really is the problem. Use
     telnet to talk to the server and find out if it is assigning a MIME
     type to the document in question. Here's an example, looking at the
     home page for my server. (idaknow: is my shell prompt)

  idaknow: telnet www.acl.lanl.gov 80  // Connect to the httpd server
  Trying 128.165.148.3 ...
  Connected to www.acl.lanl.gov.
  Escape character is '^]'.
  HEAD /Home.html  HTTP/1.0             // replace Home.html  with your 
documen
t
                                       // you supply the blank line
  HTTP/1.0 200 OK                      // the rest of this comes from the 
serve
r  Date: Wednesday, 25-May-94 19:18:11 GMT
  Server: NCSA/1.1
  MIME-version: 1.0
  Content-type: text/html              // Here's the MIME Content-type
  Last-modified: Monday, 16-May-94 16:21:58 GMT
  Content-length: 1727

  Connection closed by foreign host.
  idaknow:

     In the example above, /Home.html will get
     http://www.acl.lanl.gov/Home.html .
     
     Normally servers will be configured to supply a Content-type of
     text/plain if they don't know what else to do. If this is the
     problem you are having, take a look at the TypesConfig documentation
     for NCSA's httpd. You can have the server look at the filename
     extension, supply the correct Content-type, then use your local
     .mailcap file to tell Mosaic what viewer to use to look at the
     document.
     
   Russ Segal adds:
   
     The answer from Ronald Daniel is essentially correct, but it needs a
     small addendum.
     
     When starting Moasic, you can specify a "fileProxy" which will fetch
     files for you:
     
     "*fileProxy: http://socks/"
     
     If you do this, file: URLs are no longer strictly local accesses. So
     even if the URL is not fttp:, the proxy server must be upgraded as
     Mr. Daniel suggests.
     
   
   
4.10: Hey, I know, I'll write a WWW-exploring robot! Why not?

   Programs that automatically traverse the web can be quite useful, but
   have the potential to make a serious mess of things. Robots have been
   written which do a "breadth-first" search of the web, exploring many
   sites in a gradual fashion instead of aggressively "rooting out" the
   pages of one site at a time. Some of these robots now produce
   excellent indexes of information available on the web.
   
   But others have written simple depth-first searches which, at the
   worst, can bring servers to their knees in minutes by recursively
   downloading information from CGI script-based pages that contain an
   infinite number of possible links. (Often robots can't realize this!)
   Imagine what happens when a robot decides to "index" the CONTENTS of
   several hundred mpeg movies. Shudder.
   
   The moral: a robot that does what you want may already exist; if it
   doesn't, please study the document World Wide Web Robots, Wanderers
   and Spiders (URL is: http://web.nexor.co.uk/mak/doc/robots/robots.html
   ) and learn about the emerging standards for exclusion of robots from
   areas in which they are not wanted. You can also read about existing
   robots there.
   
4.11: How do I send newsgroup posts in HTML to my web client?

   How to do this depends greatly on your system; if you have a Mac or
   Windows system, the answer is completely different. But, as food for
   thought, here is a simple shell script I use on my Unix account to
   send posts from rn and related newsreaders to Lynx. Put this text in
   the file "readwebpost" and use the "chmod" command to make it
   executable, then put it somewhere in your path (such as your personal
   bin directory):

#!/bin/sh
echo \<PRE\> > .article.html
cat >> .article.html
echo \</PRE\> >> .article.html
lynx .article.html  < /dev/tty
rm .article.html

   Then add the following line to your .rnmac file (create it if you
   don't already have one):

W     |readwebpost %C

   Now, when you press "W" while reading a post in rn, a message will be
   sent to Lynx, and the links enclosed in it will be live.
   
   Larry W. Virden provides the following version which invokes Mosaic
   instead, and is also capable of communicating with an already-running
   copy of Mosaic instead of launching another. (You can use the same rn
   macro as above, invoking "goto-xm" instead of "readwebpost".) Read the
   comments for details on the assumptions made by the script.

#! /bin/sh
# goto-xm, by Joseph T. Buck <jbuck@eecs.berkeley.edu>
# Modified heavily by Larry W. Virden <lvirden@cas.org>
# Script for use with newsreaders such as trn.  Piping the article
# through this command causes xmosaic to pop up, pointing to the
# article.  If an existing xmosaic (version 1.1 or later) exists,
# the USR1 method will be used to cause it to point to the correct
# article, otherwise a new one will be started.

# assumptions: ps command works as is on SunOS 4.1.x, may need changes
# on other platforms.

URL=`/bin/grep '^Message-ID:' | /bin/sed -e 's/.*</news:/' -e 's/>.*//'`
if [ "X$URL" = "X" ]; then
        echo "USAGE: $0 [goto] [once] < USENET_msg" >&2
        exit 1
fi

pid=`ps -xc | egrep '[Mm]osaic' | awk 'NR == 1 {print $1}'`
p=`which Mosaic`
gfile=/tmp/Mosaic.$pid

$p "$URL" &

if      [ "$#" -gt 0 ] ; then
  if    [ "$1" = "goto" -o "$1" = "same" ] ; then
        shift
        echo "goto"   > $gfile
  else
        echo "newwin" > $gfile
  fi
else
        echo "newwin" > $gfile
fi
/bin/awk 'END { printf "'"$URL"'" }' </dev/null >> $gfile

trap "echo signal encountered" 30
kill -USR1 $pid

exit 0

   
   
   See also MosaicMail (URL is
   http://www.oac.uci.edu/indiv/ehood/mhonarc.doc.html ), a Perl script
   which pipes email and/or news to your current Mosaic session.
   
4.12: I can't get SLIP. I want Mosaic. Is there a way?

   YES! If you have a plain old Unix shell account on a Unix system, such
   as a SunOS or Ultrix system, you can do one of two things: you can run
   SlipKnot, a special browser which operates using programs that may
   already be installed on your shell account (see section 4.3.1), or you
   can run The Internet Adapter (TIA), a program which provides a
   pseudo-SLIP connection. The remainder of this section focuses on TIA.
   
   TIA is not free software, but there is a free two-week trial period
   and it is very cheap to register.
   
   "So what do I run on my machine at home?"
   
   Exactly the same software you would use for real SLIP; as far as your
   PC is concerned, it is a SLIP connection. If you're unfamiliar with
   SLIP please check out a newsgroup relevant to your particular type of
   PC (Windows, Mac, etc). (This isn't restricted to common systems;
   because all the emulation happens on your Unix shell account, your
   client machine can run anything that supports SLIP.)
   
   "Details, please! I'm confused."
   
   Check out the TIA home page (URL is
   http://marketplace.com/tia/tiahome.html ), or send email to
   info@marketplace.com and request details about TIA.
   
   If you have a Macintosh, check out the Macintosh TIA Users' FAQ (URL
   is: ftp://ftp.netcom.com/pub/bi/billa/tia/faq.html ) for additional
   help.
Archive-name: www/faq/part2
Last-modified: 1995/26/1

   
                5.1: HOW CAN I PROVIDE INFORMATION TO THE WEB?
                                       
   
   
   Information providers run programs that the browsers can obtain
   hypertext from. These programs can either be WWW servers that
   understand the HyperText Transfer Protocol HTTP (best if you are
   creating your information database from scratch), "gateway" programs
   that convert an existing information format to hypertext, or a
   non-HTTP server that WWW browsers can access -- anonymous FTP or
   gopher, for example.
   
   To learn more about World Wide Web servers, you can consult a www
   server primer by Nathan Torkington, available at the URL
   http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-servers.html .
   
   If you only want to provide information to local users, placing your
   information in local files is also an option. This means, however,
   that there can be no off-machine access.
   
5.2: Obtaining Servers

   Servers are available for Unix, Macintosh, MS Windows, Windows NT,
   OS/2, and VMS systems. If you know of a server for another operating
   system, please contact me.
   
   See http://info.cern.ch/hypertext/WWW/Daemon/Overview.html for more
   information on writing servers and gateways in general.
   
  5.2.1: UNIX SERVERS
  
   NCSA httpd
          NCSA has released a server, known as the NCSA httpd; it is
          available at the URL ftp://ftp.ncsa.uiuc.edu/Web/ncsa_httpd .
          
   EIT httpd
          EIT has created the Webmaster's Starter Kit, which installs
          their WWW server on your system via the web through a painless
          forms interface. Recommended for those unfamiliar with server
          installation. You can learn more about the starter kit and the
          EIT httpd at the starter kit site (URL is
          http://wsk.eit.com/wsk/doc/ ).
          
   CERN httpd
          CERN's server is available for anonymous FTP from info.cern.ch
          (URL is http://info.cern.ch/hypertext/WWW/Daemon/Status.html )
          and many other places. Use your local copy of archie to search
          for "www" in order to find a nearby site.
          
   GN Gopher/HTTP server
          The GN server is unique in that it can serve both WWW and
          Gopher clients (in their native modes). This is a good server
          for those migrating from Gopher to WWW, although it does not
          have the server-side-script capabilities of the NCSA and CERN
          servers. See the URL http://hopf.math.nwu.edu/ .
          
   Perl server
          There is also a server written in the Perl scripting language,
          called Plexus, for which documentation is available at the URL
          http://bsdi.com/server/doc/plexus.html .
          
   WN Server
          The WN Server, available at the URL
          http://hopf.math.nwu.edu/docs/manual.html , is designed with an
          emphasis on security and flexibility, and takes a different
          approach from the NCSA and CERN servers. It provides text
          searching facilities as a standard feature.
          
  5.2.2: MACINTOSH SERVERS
  
   There is a server for the Macintosh, MacHTTP, available at the URL
   http://www.uth.tmc.edu/mac_info/machttp_info.html .
   
  5.2.3: MS WINDOWS, IBM OS/2 AND MS WINDOWS NT SERVERS
  
   HTTPS (Windows NT)
          HTTPS is a server for Windows NT systems, both Intel and Alpha
          -- based. It is available via anonymous FTP from emwac.ed.ac.uk
          in the directory pub/https (URL is
          ftp://emwac.ed.ac.uk/pub/https). (Be sure to download the
          version appropriate to your processor.) You can read a detailed
          announcement at the FTP site, or by using the URL
          ftp://emwac.ed.ac.uk/pub/https/https.txt.
          
          A professional version is also available (URL is
          http://emwac.ed.ac.uk/html/internet_toolchest/https/prof.htm ).
          
   NCSA httpd for Windows
          The NCSA httpd for Windows has most of the features of the Unix
          version, including scripts (which generate pages on the fly
          based on user input). It is available by anonymous FTP from the
          ftp site ftp.alisa.com in the directory pub/win-httpd, and
          documentation can be found at the URL
          http://www.alisa.com/win-httpd/index.html .
          
   SerWeb
          A simple, effective server for Windows writtten by Gustavo
          Estrella. Available by anonymous ftp from
          winftp.cica.indiana.edu (or one of its mirror sites, such as
          nic.switch.ch), as the file serweb03.zip, in the directory
          /pub/pc/win3/winsock.
          
          There is also a Windows NT version of SerWeb, available by
          anonymous FTP from emwac.ed.ac.uk as /pub/serweb/serweb_i.zip.
          
   WEB4HAM
          Another Windows-based server, available by anonymous FTP from
          ftp.informatik.uni-hamburg.de as /pub/net/winsock/web4ham.zip.
          
   OS2HTTPD
          An OS/2 server, written by Frankie Fan. See the home page (URL
          is ftp://ftp.netcom.com/pub/kf/kfan/overview.html ) for
          details, or fetch the package by anonymous FTP from
          ftp.netcom.com in the directory pub/kf/kfan.
          
  5.2.4: MSDOS AND NOVELL NETWARE SERVERS
  
   KA9Q   KA9Q NOS (nos11c.exe) is a internet server package for DOS that
          includes HTTP and Gopher servers. It can be obtained via
          anonymous FTP from one of the following sites:
          

inorganic5.chem.ufl.edu
biochemistry.cwru.edu

   GLACI-HTTPD
          GLACI-HTTPD is a Netware Loadable Module which allows a Novell
          NetWare server to become a World Wide Web server (URL is
          http://www.glaci.com/info/glaci-httpd.html ).
          
   
   
  5.2.5: VMS SERVERS
  
   CERN HTTP for VMS
          A port of the CERN server to VMS. Available at the URL
          http://delonline.cern.ch/disk$user/duns/doc/vms/distribution.html .
          
   Region 6 Threaded HTTP Server
          A native VMS server which uses DECthreads(tm). This is a
          potentially major performance advantage because VMS has a high
          overhead for each process, which is a problem for the
          frequently-forking NCSA and CERN servers that began life under
          Unix. A multithreaded server avoids this overhead. Available at
          the URL http://kcgl1.eng.ohio-state.edu/www/doc/serverinfo.html .
          
   
   
  5.2.6: AMIGA SERVERS
  
   NCSA's Unix server has been ported to the Amiga, and is bundled with
   the AMosaic browser. See the URL
   http://insti.physics.sunysb.edu/AMosaic/home.html for details.
   
  5.2.7: VM/CMS SERVERS
  
   A VM/CMS web server is available; see the URL
   http://ua1vm.ua.edu/~troth/rickvmsw/rickvmsw.html for more
   information. If you don't yet have a web browser to try this URL with,
   check out the VM/CMS Browsers section.
   
  5.2.8: YEAH, BUT WHICH IS BEST?
  
   
   
   To find out which server is best for your needs, you will want to
   consult Paul Hoffman's Server Comparison Chart (URL is
   http://sunsite.unc.edu/boutell/faq/chart.html ). That document is also
   available by anonymous FTP from ftp.netcom.com in the directory
   pub/bo/boutell/faq.
   
5.3: Producing HTML documents

   HTML is the simple markup system used to create hypertext documents.
   There are three ways to produce HTML documents: writing them yourself,
   which is not a very difficult skill to acquire, using an HTML editor,
   which assists in doing the above, and converting documents in other
   formats to HTML. The following three sections cover these
   possibilities in sequence.
   
  5.3.1: WRITING HTML DOCUMENTS YOURSELF
  
   You can write an HTML document with any text editor. Try the "source"
   button of your browser (or "save as" HTML) to look at the HTML for a
   page you find particularly interesting. The odds are that it will be a
   great deal simpler than you would expect. If you're used to marking up
   text in any way (even red-pencilling it), HTML should be rather
   intuitive.
   
   A beginner's guide to HTML is available at the URL
   http://www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimer.html . You
   can also find a plain text version (at the URL
   ftp://ftp.ncsa.uiuc.edu/ncsapubs/WWW/HTMLPrimer.txt) and a compressed
   Postscript version (at the URL
   ftp://ftp.ncsa.uiuc.edu/ncsapubs/WWW/HTMLPrimer.ps.Z). (Since the
   latter two are FTP URLs, you can fetch them by hand using FTP if you
   do not yet have a web browser.)
   
   There is also an HTML primer by Nathan Torkington at the URL
   http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-html.html .
   
  5.3.2: HTML EDITORS
  
   Of course, most folks would still prefer to use a friendlier,
   graphical editor. Some editors are WYSIWYG (What You See Is What You
   Get), or close to it; others simply assist you in writing HTML by
   plugging in the desired markup tags for you from a menu.
   
   Fans of the EMACS editor can use EMACS and html-helper-mode , an EMACS
   "mode" for HTML editing (URL is http://www.reed.edu/~nelson/tools/ ).
   
   There is also another Emacs HTML mode, html-mode.el (URL is
   ftp://ftp.ncsa.uiuc.edu/Web/html/elisp/html-mode.el ).
   
   For Microsoft Windows users, there is an editor called HTML Assistant
   with features to assist in the creation of HTML documents. It can be
   had by anonymous FTP from ftp.cs.dal.ca in the directory /htmlasst/.
   Read the README.1ST file in this directory for information on which
   files to download.
   
   ANT_HTML.DOT is a Word for Windows 6.0 template designed to convert
   Word documents into HTML documents in a WYSIWYG environment. It
   includes a demo version of the ANT_PLUS utility, which converts HTML
   files to WYSIWYG. ANT_PLUS also converts HTML files to ASCII, RTF, or
   any other format possible in Word 6.0. Contact jswift@freenet.fsu.edu
   if you need more information.
   
   A WYSIWYG editor for the Web, SoftQuad HoTMetaL, is available for
   downloading at NCSA and numerous other sites. Many mirror sites exist;
   if you can't get through to one, try another, don't give up! That's
   what mirror sites are for. (Also be sure to use the copy closest to
   you geographically if possible.) Hotmetal is available for both Sun
   Sparc systems and Windows systems; note that Windows users need at
   least 6 megabytes of free memory. (A 2-megabyte swap file should just
   barely do the trick on a 4MB machine.)
   
   Known mirrors:
     * ftp://ftp.ncsa.uiuc.edu/Web/html/hotmetal/
     * ftp://ftp.ifi.uio.no/pub/SGML/HoTMetaL
     * ftp://sgml1.ex.ac.uk/SoftQuad
     * ftp://src.doc.ic.ac.uk/packages/WWW/ncsa/html/hotmetal/
     *
       ftp://askhp.ask.uni-karlsruhe.de/pub/infosystems/mosaic/contrib/Sof
       tQuad
     * ftp://ftp.cs.concordia.ca/pub/www
     *
       
   You need a Sun SPARC or Microsoft Windows system and 6MB of disk (6MB
   of RAM minimum for MS Windows; swap files count). Other Unix systems
   may be supported by the time you read this; have a look on one of the
   sites above.
   
   Because it is context-sensitive, HoTMetaL guides users in creating new
   HTML documents and in cleaning up old ones. A Publish command changes
   appropriate SRC and HREF attributes from local paths to http
   locations. For more information, FTP the README file from the same
   directory, or send email to hotmetal@sq.com. A HoTMetaL Pro
   commercially supported version is available for purchase from SoftQuad
   and its resellers.
   
   Also see Gabriel White's reviews of MS Windows HTML editors (URL is
   http://werple.mira.net.au/%7Egabriel/web/html/editors/ ). Another
   option, if you have an SGML editor, is to use it with the HTML DTD
   (URL is http://info.cern.ch/hypertext/WWW/MarkUp/DTDHeading.html ).
   
   An editor for all X users: TkWWW (listed above under X browsers)
   supports WYSIWYG HTML editing; and since it's a browser, you can try
   out links immediately after creating them.
   
   Another editor for X users: Phoenix (URL is
   http://www.bsd.uchicago.edu/ftp/pub/phoenix/README.html ) is a fully
   WYSIWYG HTML editor which insulates the user from direct control of
   the HTML tags. Available by anonymous FTP from www.bsd.uchicago.edu in
   the pub/phoenix subdirectory.
   
   Also for X users, there is a package called htmltext which supports
   WYSIWYG HTML editing. More information is available at the URL
   http://web.cs.city.ac.uk/homes/njw/htmltext/htmltext.html .
   
   For Macintosh users, there is a near-WYSIWYG package called HTML
   Editor (URL is http://dragon.acadiau.ca:1667/~giles/HTML_Editor).
   
   ANT_HTML is a Word for the Macintosh template designed to convert Word
   documents into HTML documents in a WYSIWYG environment. It includes a
   demo version of the ANT_PLUS utility, which converts HTML files to
   WYSIWYG. ANT_PLUS also converts HTML files to ASCII, RTF, or any other
   format possible in Word. At the time of this writing it was scheduled
   to have been released on the Macintosh (it has long been available for
   Windows). Contact jswift@freenet.fsu.edu for more information. Also
   for Macintosh users, the BBEdit HTML extensions allow the BBEdit and
   BBEdit Lite text editors for the Macintosh to conveniently edit HTML
   documents. (URL is http://www.uji.es/bbedit-html-extensions.html .)
   You can also obtain the extensions package by anonymous ftp from
   sumex-aim.stanford.edu as info-mac/bbedit-html-ext-b3.hqx.
   
   There is an alternative BBEdit extension package available as well
   (URL is http://www.york.ac.uk/~ld11/BBEditTools.html ). it is
   available by FTP from ftp.york.ac.uk in the directory
   /pub/users/ld11/BBEdit_HTML_Tools.sea.hqx.
   
   NCSA's List of Filters and Editors, for which the URL is
   http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/faq-software.html#ed
   itors, mentions several editors, including two for MS Windows. In some
   cases, the "editor" amounts to a set of macros for an existing word
   processor, which can provide a near-WYSIWYG environment.
   
   Note that this URL contains uppercase and lowercase letters; certain
   operating systems won't allow mixed case on the command line, or will
   only allow it if it is quoted (VMS), so if you are launching Lynx or
   another client and specifying a URL at the command line, try quoting
   the URL in double-quotes ("URL").
   
  5.3.3: CONVERTING OTHER FORMATS TO HTML
  
   There is a collection of filters for converting your existing
   documents (in TeX and other non-HTML formats) into HTML automatically,
   including filters that can allow more or less WYSIWYG editing using
   various word processors:
   
   Rich Brandwein and Mike Sendall's List at CERN (URL is
   http://info.cern.ch/hypertext/WWW/Tools/Filters.html ).
   
   (Note that this URL contains uppercase and lowercase letters; certain
   operating systems such as VMS require you to quote mixed-case URLs
   when launching a borwser from the command line. This is NOT a bug in
   the browser.)
   
   There is also a Word for Windows template for writing HTML documents,
   available at the URL http://www.gatech.edu/word_html/release.htm .
   
  5.3.4: CHECKING YOUR HTML FOR ERRORS
  
   Tools to validate your HTML documents (check them for errors) are
   available. There is a form at the URL
   http://www.hal.com/%7Econnolly/html-test/service/validation-form.html
   which will check HTML documents for errors according to the latest
   specification; note that you are encouraged to set up the program on
   your own system if you make heavy use of the form. There is also a
   tool which will check the links in your documents for links to
   nonexistent resources, such as pages that have moved (URL is
   http://wsk.eit.com/wsk/dist/doc/admin/webtest/verify_links.html ).
   
   Also try weblint (URL is
   http://www.khoros.unm.edu/staff/neilb/weblint.html ), a Perl script
   that checks your HTML for errors; you can even try it out over the web
   through an HTML form. The script is available by anonymous FTP from
   ftp.khoros.unm.edu in the directory pub/perl/www.
   
   Another such tool is htmlchek (URL is:
   http://uts.cc.utexas.edu/~churchh/htmlchek.html ), which checks HTML
   documents for errors, creates a cross-reference, automatically expands
   entities (such as European characters) to their proper HTML form, and
   performs other useful services. htmlchek is available by anonymous FTP
   from ftp.cs.buffalo.edu in the directory pub/htmlchek.
   
5.4: How do I publicize my work?

   There are several things you can do to publicize your new HTML server
   or other offering:
     * Post to comp.infosystems.www.announce. PLEASE READ THE CHARTER
       POSTING FIRST. In general, always read a newsgroup first to
       familiarize yourself before posting to it.
     * Submit it to the NCSA What's New Page at the URL
       http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html
       (see the page for details on how to submit your listing!).
     * Post it to the newsgroup comp.infosystems.announce. Please read
       the group first to get a feel for the contents. You should not
       post to comp.infosystems.www.users,.misc,.providers, etc., but if
       you feel compelled to do so, please choose .misc as announcements
       are of interest to both providers and users (and those who wear
       both hats).
     * Submit it to the maintainers of various catalogs, such as the WWW
       Virtual Library (at the URL
       http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html
       ) and the ALIWEB index (at the URL
       http://web.nexor.co.uk/aliweb/doc/aliweb.html ).
     * Read Gareth Rees' guide to publishing on the World Wide Web. (URL
       is http://www.cl.cam.ac.uk/users/gdr11/publish.html ).
       
5.5: Can I buy space on an existing server?

   Yes, you can. A list of sites offering WWW space for lease is
   available (at the URL http://union.ncsa.uiuc.edu/www/leasing.shtml ).
   
5.6: How fast does my net connection need to be?

   The following response to this very-frequently-asked-question was
   provided by Mike Meyer (mwm@contessa.phone.net).
   
     The answer is "It depends." What it depends on is what kind of
     things you want to provide on your server. Here are some rules of
     thumb to use when deciding what kind of connection you need for your
     server.
     
     The first rule of thumb is:
     
     Don't worry about simultaneous access.
     
     Unless you have a very large site, simultaneous access is not a
     problem. If you have a very large site, you need as much bandwidth
     as you can afford. There is a bit more about this below.
     
     The second rule of thumb is:
     
     It should take at most 5 seconds to send a page.
     
     The five second rule dates from command line days, when that was
     about how long people would wait before getting impatient with the
     system. It seems like a reasonable number to use now.
     
     Since external images/audio/etc. are somewhat exceptional, allow
     more time for them. If you think they should have the same
     restrictions as above, buy the bandwidth your site will need to do
     so. However, the rule of thumb for external images/audio/etc is:
     
     It should take at most 30 seconds to send an external file.
     
     Given these rules, it's pretty straightforward to work out how large
     an HTML page and external files can be. At least, it's easy after
     you simplify things by ignoring IP overhead on the line, compression
     on modem lines, and anything that's less than 10% of the total (or
     even a little bit more than 10%).
     
     The one simplification not to ignore is the multiple packet
     round-trips it takes to get data flowing through an HTTP channel.
     For modem lines, this is nearly a second for each HTTP connection,
     which is significant. For leased lines, it's more like .1 or .2
     seconds, which is not significant.
     
     On a 14.4 line assumed to be sending 1.4K bytes of data/second, with
     a 1 second startup, you get 4 * 1.4 or 5.6K of HTML. If you want to
     include a single inline image, that's 2 seconds of startup, so
     you're down to 3 * 1.4 or 4.2K of HTML + image. This means smallish
     HTML pages, and simple inline images. For external files, you get 29
     * 1.4 or 40K, which is still a small image. If you have a 28.8 line,
     you get to double those figures; for a 9600 line, figure 2/3rds of
     that size.
     
     On a 56K leased line assumed to be sending 5K/second, you get 25K of
     HTML, or mixed HTML/data. For external images, it's 150K. That
     should cover any reasonable HTML document, and small to medium
     external files. An MPEG movie might be a bit much.
     
     With a T1 line assumed to be sending 150K/second, you get 750K of
     HTML, or 4.5 megabytes in an external file. Barring very large
     animations, this should be sufficient for anything you want to
     serve. More would be faster, but it also gets drastically more
     expensive.
     
     Given the above guidelines, let's look at simultaneous access again.
     Under the worst case conditions, you're using all of your line for
     HTML pages, each of which takes 5 seconds to send, so your server is
     sending 12 pages a minute, or 720 pages an hour, or 17,000 pages a
     day (pages, not accesses; each inline image in a page generates an
     access, unless the client cached it). This makes you one of the
     busier sites on the web. While you'll have contention problems
     before you get to this point, anything but a modem connection will
     be sending most pages in a small fraction of five seconds, which
     should leave plenty of bandwidth with no contention. If you have
     this kind of access rates on a modem line, you should seriously
     consider upgrading your connection.
     
     The bottom line on simultaneous access is that the WWW server is
     more likely to have contention with other uses of the line than with
     itself. Since I don't know what else you use your line for, I can't
     factor it in. You'll have to consider that issue yourself.
     
   
   
  5.7.1: HOW DO I SET UP A CLICKABLE IMAGE MAP?
  
   
   
   There are really two issues here: how to indicate in HTML that you
   want an image to be clickable, and how to configure your server to do
   something with the clicks returned by Mosaic, Chimera, and other
   clients capable of delivering them.
   
   You can read about image maps and the NCSA server at the URL
   http://hoohoo.ncsa.uiuc.edu/docs/setup/admin/Imagemap.html .
   
   Using imagemaps requires that you create a map file; you can do this
   by hand or with a WYSIWYG tool.
   
   VERY IMPORTANT: Creating imagemaps requires a real web server (not
   an FTP server) and a cooperative web server administrator. It is not
   usually as simple as wrapping a link around an IMG SRC tag and adding
   the ISMAP directive; the server must also be told about the map file,
   and the way to accomplish this varies from server to server. So read
   your server documentation, and don't waste time making maps before
   making sure you have the necessary tools to deliver them.
   
   Mapedit
          Mapedit (URL is:
          http://sunsite.unc.edu/boutell/mapedit/mapedit.html ) is a
          WYSIWYG imagemap editing tool for Microsoft Windows and the X
          Window System.
          
   MapMaker
          For users of John Bradley's xv image display software for the
          X Window System, Mapmaker can turn the miniature images created
          by xv's Visual Schnauzer into an imagemap. This is useful if
          you would like to make an entire directory of images available
          (but note that you should also make textual links to allow
          those with text- based browsers to download the images for
          external viewing). (URL is:
          http://icg.stwing.upenn.edu:80/~mengwong/mapmaker.html )
          
   WebMap
          On the Macintosh, you may want to use WebMap (URL is
          ftp://ftp.uwtc.washington.edu/pub/Mac/Network/WWW ). . It
          produces both NCSA and CERN-compatible maps, which can also be
          used with MacImagemap and a Macintosh-based server (MacImagemap
          is found in the same directory). Alternatively, you may want to
          use MacMapMaker, also available from
          ftp://ftp.uwtc.washington.edu/pub/Mac/Network/WWW (the same
          directory).
          
   Tkmapedit
          For Unix systems and other systems on which the Tk/Tcl language
          toolkit has been installed, Tkmapedit provides a WYSIWYG
          imagemap editor which is capable of directly testing links if
          the tkWWW web browser is available. Available by anonymous FTP
          from the TCL archive on ftp.aud.alcatel.com.
          
   
   
  5.7.2: HOW DO I MAKE A "LINK" THAT DOESN'T LOAD A NEW PAGE?
  
   
   
   Such links are useful when a form is intended to perform some action
   on the server machine without sending new information to the client,
   or when a user has clicked in an undefined area in an image map; these
   are just two possibilities.
   
   Rob McCool of NCSA provided the following wisdom on the subject:

Yechezkal-Shimon Gutfreund (sg04@gte.com) wrote:
: Ok, here is another bizzare request from me:

: I am currently running scripts which I "DO NOT" want to return
: any visible result. That is, not text/plain, not text/HTML, not
: image/gif. The entire results are the side effects of the
: script and nothing should be returned to the viewer.

: It would be nice to have an internally supported null viewer
: so that I could do this, more "cleanly" (ok, ok, I hear your groans).

   
   
   HTTP now supports a response code of 204, which is no operation. Some
   browsers such as Mosaic/X 2.* support it. To use it, make your script
   a nph script and output an HTTP/1.0 204 header. Something like:
   
   HTTP/1.0 204 No response Server: Myscript/NCSA httpd 1.1
   
   (You can learn more about nph scripts from the NCSA server
   documentation at the URL http://hoohoo.ncsa.uiuc.edu/docs .)
   Essentially they are scripts that handle their own HTTP response
   codes.
   
  5.7.3: WHERE CAN I LEARN HOW TO CREATE FILL-OUT FORMS?
  
   Writing an HTML form is easy, but the form doesn't accomplish anything
   until you write a CGI program to interpret the results on the server
   side! For more information, see section 5.7.14.
   
   See the section on email forms for a simple solution to the most
   commonly desired form.
   
    5.7.3.1: How can I create hidden fields in forms (keeping state)?
    
   Use INPUT TYPE=hidden. An example:

<INPUT TYPE=hidden NAME=state VALUE="hidden info to be returned with form">

   By now, most browsers can handle the hidden type, but understand that
   some browsers will fail to hide the field (and probably confuse the
   user). Note that "hidden" doesn't mean "secret"; the user can always
   click on "view source".
   
    5.7.3.2: How can users send me email through their browsers?
    
   There are two ways:
   
   Using a mailto: URL
          You can simply create a link which looks like this:
          
          <A HREF="mailto:me@my.address">Send Me Mail</A>
          
          This works great for browsers that support the mailto: URL.
          Perhaps 80% of web users will be able to use such a link. But
          not all browsers support it.
          
   Installing an email form
          If you have access to the server's configuration files, or if
          your server administrator permits users to create their own CGI
          scripts, you can create a form which sends mail to you from any
          browser that supports forms. I've written a simple email forms
          package (URL is: http://siva.cshl.org/email/index.html ), which
          does it in ANSI C. There is also a package written in Perl,
          known as the WWW Mailto Gateway (URL is
          http://www.mps.ohio-state.edu/mailto/mailto_info.html ).
          GetComments (URL is:
          http://everest.cs.ucdavis.edu/~hoagland/getcomments.html) is a
          more general package, also written in Perl, which can handle
          many different types of comment forms.
          
          If you want to learn how these forms actually work, see section
          5.7.14.
          
   
   
  5.7.4: HOW DO I COMMENT AN HTML DOCUMENT?
  
   
   
   Use the <!-- tag at the beginning of EACH line commented out; close
   this for EACH line with the --> tag. Note that comments do not nest,
   and the sequence "--" may not appear inside a comment except as part
   of the closing --> tag. (It's officially allowed, but some browsers
   won't handle it properly.)
   
   You should not try to use this to "comment out" HTML that would
   otherwise be shown to the user, since some browsers (notably Mosaic)
   will still pay attention to tags inside the comment and close it
   prematurely.
   
   Thanks to Joe English for clearing up this issue.
   
  5.7.5: HOW CAN I CREATE DECENT-LOOKING TABLES AND STOP USING <PRE>... 
</PRE>?
  
   Tables are a standard feature in HTML Level 3, a new version of HTML.
   Unfortunately, they are at present implemented only by the latest NCSA
   Mosaic versions and the Viola and Emacs-W3 browsers, to my knowledge.
   In addition, most implementations are incomplete. In some
   implementations, at the time of this writing, text in tables cannot be
   selected and/or cannot be a link.
   
   However, there is a way to use HTML Level 3 tables now and convert
   them automatically to HTML, allowing you to design proper tables and
   install those pages directly when table support arrives in the
   majority of clients. You can do this using the html+tables package, by
   Brooks Cutter (bcutter@paradyne.com), which is available for anonymous
   ftp from sunsite.unc.edu in the directory
   pub/packages/infosystems/WWW/tools/html+tables.shar. This package
   requires the shell language Perl, which is primarily used on Unix
   systems but is also available for other systems (such as MSDOS
   machines). html+tables accepts HTML Level 3 and outputs html using the
   <PRE>...</PRE> construct to represent tables, allowing you to write
   HTML Level 3 now, knowing that it will look better when clients are
   ready for it.
   
  5.7.6: WHAT IS HTML LEVEL 3 AND WHERE CAN I LEARN MORE ABOUT IT?
  
   HTML Level 3, also known as HTML+, is an enhanced version of HTML
   designed to address some of the limitations of HTML. HTML Level 3
   supports true tables, right-justified text, centered text, line breaks
   that do not double space, and many other desired features.
   
   However, most clients support only a handful of HTML Level 3 features
   (such as the partial implementation of tables in Mosaic) at the time
   of this writing. If you have access to a Unix system with the X Window
   System installed, you can try out many features of HTML Level 3 using
   the experimental Arena browser.
   
   You can access information about new developments in HTML at the CERN
   server (at the URL
   http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html ).
   
   (HTML Level 1 is the original version. HTML Level 2 is essentially the
   same, but with the addition of forms.)
   
  5.7.7: HOW CAN I MAKE TRANSPARENT AND INTERLACED GIFS? AND WHAT ARE THEY?
  
   Transparent GIFs are useful because they appear to blend in smoothly
   with the user's display, even if the user has set a background color
   that differs from that the developer expected. They do this by
   assigning one color to be transparent -- if the web browser supports
   transparency, that color will be replaced by the browser's background
   color, whatever it may be.
   
   Interlaced GIFs appear first with poor resolution and then improve in
   resolution until the entire image has arrived, as opposed to arriving
   linearly from the top row to the bottom row. This is great to get a
   quick idea of what the entire image will look like while waiting for
   the rest. This doesn't do much for you if your web browser doesn't
   support progressive display as the image is downloaded, but
   non-progressive-display web browsers will still display interlaced
   GIFs once they have arrived in their entirety.
   
   To create transparent and interlaced GIFs, check out David Koblas'
   giftool, a program which can manipulate those options and many more
   aspects of your GIF file.
   
   In addition, there is a document explaining transparent GIFs available
   at the URL http://melmac.corp.harris.com/transparent_images.html . You
   can fetch the program giftrans by anonymous ftp from
   ftp.rz.uni-karlsruhe.de at the path /pub/net/www/tools/giftrans.c.
   
   There is also a Perl Script (URL is:
   http://www.omron.co.jp:80/~jfriedl/perl/ ) which makes transparent
   GIFs.
   
   There is also a utility for the Macintosh, Transparency (URL is:
   http://www.med.cornell.edu/~giles/projects.html#transparency).
   
  5.7.8: HOW COME MAILTO: URLS DON'T WORK?
  
   The mailto: URL is a feature found in Lynx, Netscape, Spry Mosaic, the
   latest NCSA Mosaics, Emacs w3 mode and many other browsers. In
   general, about 80% of web browsers support mailto: at the time of this
   writing. However, it is not in numerous older browsers. In the
   meantime, you can set up forms which send mail to you; see Section
   5.7.3.2.
   
  5.7.9: HOW CAN I RESTRICT AND CONTROL ACCESS TO MY SERVER?
  
   All major servers have features that allow you to limit access to
   particular sites, and many clients have authentication features that
   allow you to identify specific users. There is a tutorial on security
   and user authentication with the NCSA server and Mosaic available,
   written by Marc Andreessen (URL is
   http://wintermute.ncsa.uiuc.edu:8080/auth-tutorial/tutorial.html ).
   See your server documentation for further information.
   
  5.7.10: WHICH FORMAT IS BETTER FOR WWW IMAGE PURPOSES, JPEG OR GIF?
  
   
   
   JPEG does a better job with realistic images such as scanned
   photographs. Most browsers cannot handle inline JPEGs, however, so you
   must link to them as external images (using a regular <A HREF...>
   instead of <IMG SRC...>).
   
   GIF does a better job with crisp, sharp images, such as those
   typically used to construct buttons, graphs and the like. All browsers
   that can display graphics at all can display GIFs inline.
   
  5.7.11: HOW CAN I MIRROR PART OF ANOTHER SERVER?
  
   Scripts are available to do this, but at this time they are not very
   friendly to the server you are attempting to mirror; their behavior
   resembles that of the more poorly written WWW robots. If you are
   trying to improve access times to a distant server, you will likely
   find the "proxy" capabilities of CERN's WWW server to be a more
   effective and general solution to your problem.
   
  5.7.12: HOW CAN I KEEP ROBOTS OFF MY SERVER?
  
   Programs that automatically traverse the web can be quite useful, but
   have the potential to make a serious mess of things. Every so often
   someone will write a "depth-first" searching robot that brings servers
   to their knees. See the section on writing robots (4.10) for details.
   
   Fortunately, most robots on the web follow a simple protocol by which
   you can keep them off your server if you wish, or keep them out of
   portions of your server which are robot traps (ie, they contain an
   infinite number of possible links). Read the document World Wide Web
   Robots, Wanderers and Spiders (URL is:
   http://web.nexor.co.uk/mak/doc/robots/robots.html ) and learn about
   the emerging standards for exclusion of robots from areas in which
   they are not wanted. You can also read about existing robots there,
   including useful cataloging robots you probably do not want to keep
   off your server.
   
  5.7.13: HOW CAN I KEEP STATISTICS ABOUT MY WEB SERVER?
  
   There are several tools which can generate statistics about your web
   server:
   
   getstats
          getstats is a versatile log analyzer, also written in C, which
          provides reports for various time periods with a high degree of
          flexibility. Add-on packages have been written to generate
          reports in HTML and also to generate graphs. You can access the
          getstats home page for more information (URL is
          http://www.eit.com/software/getstats/getstats.html ), or obtain
          the package by anonymous FTP from ftp.eit.com in the directory
          /pub/web.software/getstats.
          
   WebStat
          WebStat is a package written in the language Python which
          supplies statistics on usage by domain, country, etc., with
          daily, weekly, monthly and annual reports available. You will
          need Python in order to use it. See the WebStat home page (URL
          is
          
http://www.pegasus.esprit.ec.org/people/sijben/statistics/advertisment.html
          ) for details, or obtain Python from ftp.cwi.nl in
          the directory /pub/python and WebStat from
          ftp.pegasus.esprit.ec.org in the directory /pub/misc.
          
   Wusage
          Wusage, which I wrote, is a C program which generates simple
          weekly reports in HTML, with inline image graphs displaying
          server growth and the distribution of accesses by continent.
          You can also exclude irrelevant accesses (inline images, local
          machines, etc.) from the results. Read the Wusage home page
          (URL is http://siva.cshl.org/wusage.html ) for more
          information, or obtain Wusage by anonymous FTP from
          isis.cshl.org in the directory pub/wusage.
          
   wwwstat
          wwwstat is a full-featured log analyzer written in the language
          Perl. (See the newsgroup comp.lang.perl for more information
          about the language.) See the wwwstat home page (URL is
          http://www.ics.uci.edu/WebSoft/wwwstat/ ) for more information,
          or obtain the package by anonymous FTP from liege.ics.uci.edu
          in the directory /pub/arcadia/wwwstat. See also gwstat (URL is
          http://dis.cs.umass.edu/stats/gwstat.html ), a package which
          produces GIF graphs from the output of wwwstat.
          
   
   
  5.7.14: I WANT TO GENERATE WEB PAGES FROM A PROGRAM. DO I HAVE TO WRITE A
  CUSTOM SERVER?
  
   No, you will not need to write a custom server. Most web servers
   support one variation or another of a standard for adding your own
   programs to the web server. The standard is called CGI (Common Gateway
   Interface).
   
   Marc Hedlund has written a FAQ on CGI programming (URL is:
   http://www.halcyon.com/hedlund/cgi-faq/ ) which makes a good
   introduction to the subject. The standard itself can be found at NCSA
   (URL is: http://hoohoo.ncsa.uiuc.edu/ ).
   
    5.7.14.1: How can I generate GIFs on the fly from my CGI scripts?
    
   If you want to generate GIF images on the fly as part of your
   application, examine the gd library (URL is:
   http://siva.cshl.org/gd/gd.html ). Hint: your HTML page and your
   inline images are separate documents with separate URLs. Generate them
   in response to separate requests! (Yes, there are tricks to speed this
   up, but be careful not to break inline images on HTML pages you didn't
   write that refer to your gd-generated image.)
   
   It's also possible to use gnuplot and the pbmplus utilities. This is
   slower, but can require less programming if gnuplot is sufficient for
   your purposes. (See archie for both tools.)
   
                  6: WHERE CAN I DISCUSS THE WORLD WIDE WEB?
                                       
6.1: What newsgroups discuss the Web?

   You can find discussion of World Wide Web topics in three newsgroups,
   and one newsgroup which will soon be removed:
   
   comp.infosystems.www.users
          A forum for the discussion of WWW client software and its use
          in contacting various Internet information sources. New user
          questions, client setup questions, client bug reports,
          resource-discovery questions on how to locate information on
          the web that can't be found by the means detailed in the FAQ
          and comparison between various client packages are among the
          acceptable topics for this group. Please specify what browser
          and what system type (Windows, Mac, Unix, etc.) your post is
          about if you are asking questions about a specific program.
          
   comp.infosystems.www.providers
          A forum for the discussion of WWW server software and the use
          of said software to present information to users. General
          server design, setup questions, server bug reports, security
          issues, HTML page design and other concerns of information
          providers are among the likely topics for this group.
          
   comp.infosystems.www.misc
          A forum for general discussion of WWW (World Wide Web)- related
          topics that are NOT covered by the other newsgroups in the
          hierarchy. This will likely include discussions of the Web's
          future, politicking regarding changes in the structure and
          protocols of the web that affect both clients and servers, et
          cetera.
          
   comp.infosystems.www.announce
          A moderated forum for the announcement of new and updated World
          Wide Web resources and software.
          
   comp.infosystems.www (DEFUNCT)
          The old catch-all newsgroup, which may still exist on your
          system but was officially removed on September 7th, 1994,
          according to David Lawrence, moderator of
          news.announce.newgroups. If your system still carries this
          group, ask your administrator to remove it.
          
   
   
6.2: What mailing lists discuss the Web?

   www-talk@info.cern.ch
          Address: www-talk@info.cern.ch for CONTRIBUTIONS ONLY.
          Administration: listserv@info.cern.ch (robot)
          www-talk-request@info.cern.ch (human). Description: Technical
          discussion, W3 related. Experts to experts. General questions
          to the newsgroups, please. Archive: Not currently served, but
          kept.
          
   www-announce@info.cern.ch
          Address: www-announce@info.cern.ch. NOT FOR GENERAL USE -
          serious low-volume announcements only. Administration:
          listserv@info.cern.ch (robot),
          www-announce-request@info.cern.ch (human). Description: Low
          volume summary announcemements of product releases, etc.
          Archive: Not currently public.
          
   
   
                            7: I WANT TO KNOW MORE
                                       
   
   
   To find out more, use the web. This FAQ hopefully provides enough
   information for you to locate and install a browser on your system. If
   you have system specific questions regarding FTP, networking and the
   like, please consult newsgroups relevant to your particular hardware
   and operating system!
   
   Once you're up and running, you may wish to consult the World Wide Web
   Primer by Nathan Torkington. It is available at the URL
   http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-primer.html .
   
   Later you may return to this FAQ for answers to some of the more
   advanced questions. I encourage you to check out the changes listed
   early in the document each time the FAQ appears.
   
                                  8: CREDITS
                                       
   Maintainer (11/93 to present): Thomas Boutell, boutell@netcom.com
   
   Former Maintainer (until 11/93): Nathan Torkington,
   Nathan.Torkington@vuw.ac.nz
