FAQ: Frequently Asked Questions about World Wide Web
Thomas Boutell
************************
Contents
========
o 1. Recent changes to the FAQ
o 2. Information about this document
o 3. What are WWW, hypertext and hypermedia?
o 4. What is a URL?
o 5. How can I access the web?
o 5.1 Browsers accessible by telnet
o 5.2 Obtaining browsers
o 6. How can I provide information to the web?
o 7. How does WWW compare to gopher and WAIS?
o 8. What is on the web?
o 9. I want to know more.
o Z. Credits
1. Recent changes to the FAQ
============================
o New FAQ maintainer (Thomas Boutell)
o List of browsers updated
o FTP access information added for browsers
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 "Big Dummy's Guide to the Internet". The
latter is available electronically by anonymous FTP from ftp.eff.org
in the directory pub/Net_info/Big_Dummy.
This informational document is posted to news.answers,
comp.infosystems.www, comp.infosystems.gopher,
comp.infosystems.wais and alt.hypertext on the 1st and 15th of
every month (please allow a day or two for it to propagate to your
site). The latest version is always available on the web as
http://siva.cshl.org/~boutell/www_faq.html. (see the section titled
"What is a URL?" to understand what this means.)
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 (the URL for this is
file://rtfm.mit.edu/pub/usenet/news.answers/www/faq). For
information on FTP, send e-mail to mail-...@rtfm.mit.edu
with "send usenet/news.answers/finding-sources" in the body,
instead of asking me.
Thomas Boutell maintains this document. Feedback about it is to
be sent via e-mail to bou...@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In all cases, regard this document as out of date.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. Please excuse any
formatting inconsistencies in the posted version of this document,
as it is automatically generated from the on-line version.
3. 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.
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.
4. 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:
o file://wuarchive.wustl.edu/mirrors/msdos/graphics/gifkit.zip
o file://wuarchive.wustl.edu/mirrors
o http://info.cern.ch:80/default.html
o news:alt.hypertext
o 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). For more
information, see
5. How can I access the web?
****************************
You have two options -- either use a browser that can be
telnetted to, or use a browser on your machine.
5.1 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.
info.cern.ch
No password is required. This is in Switzerland, so
continental US users might be better off using a closer
browser.
ukanaix.cc.ukans.edu
A full screen browser "Lynx" which requires a vt100
terminal. Log in as www.
www.njit.edu
(or telnet 128.235.163.2) Log in as www. A full-screen
browser in New Jersey Institute of Technology. USA.
vms.huji.ac.il
(IP address 128.139.4.3). 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 info. Not working.
fserv.kfki.hu
Hungary. Has slow link, use from nearby. Login is as www.
5.2 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.
Terminal based browsers
+++++++++++++++++++++++
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.
"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
W3 browse mode for emacs. Uses multiple fonts when
used with Lemacs or Epoch. See doc . Available by
anonymous FTP from moose.cs.indiana.edu in the
directory pub/elisp/w3 as the files w3.tar.Z and extras.tar.Z.
PC Running Windows
==================
NOTE: both of these browsers require that you have SLIP or
TCP/IP networking on your PC. SLIP can be accomplished over
phone lines, but only with the active cooperation of your network
provider or educational institution. If you only have normal dialup
shell access, your best option at this time is to run Lynx on the
system you call.
Cello
Browser from Cornell LII. Available by anonymous FTP
from fatty.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/Mosaic.
Macintosh
=========
NOTE: all of these browsers require that you have SLIP or
TCP/IP networking on your PC. SLIP can be accomplished over
phone lines, but only with the active cooperation of your network
provider or educational institution. If you only have normal dialup
shell access, your best option at this time is to run Lynx on the
system you call.
Mosaic for Macintosh
From NCSA. Full featured. Available by anonymous FTP
from ftp.ncsa.uiuc.edu in the directory Mac/Mosaic.
Samba
From CERN. Basic. Available by anonymous FTP from
info.cern.ch in the directory /ftp/pub/www/bin as the file
mac.
XWindows
========
NCSA Mosaic for X
Browser using X11/Motif. Multimedia magic. Full http 1.0
support including PUT-method forms, image maps, etc.
Recommended if you can run it. Available by anonymous
FTP from ftp.ncsa.uiuc.edu in the directory Mosaic.
tkWWW Browser/Editor for X11
Browser/Editor for X11. (Beta test version.) Available for
anonymous ftp from export.lcs.mit.edu in the directory
contrib as tkWWW-0.10.tar.Z. (Note: this document may
be up to date, so you may prefer to ftp to this site by hand
and look for an even newer version rather than using the
link above.)
MidasWWW Browser
From Tony Johnson. (Beta, works well.)
Chimera
Browser using Athena (doesn't require Motif). Available
for anonymous FTP from ftp.cs.unlv.edu in the directory
/pub/chimera.
NeXTStep
========
Browser-Editor on the NeXT
A browser/editor for NeXTStep. Allows wysiwyg
hypertext editing. Requires NeXTStep 3.0. Available for
anonymous FTP from info.cern.ch in the directory
/pub/www/src.
Unreleased or Unsupported
=========================
Browser on CERNVM
A full-screen browser for VM. Nonexistent. Use the line
mode www. Might arrive suddenly one day.
Dave Ragget's Browser
Unreleased. For X11, (later PC?)
Erwise
X-windows early browser. Unsupported, now of historical
interest only.
NJIT's Browser
Assumes a character-grid terminal with cursor addressing, and
provides a full-screen interface to the web.
6. 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.
If you only want to provide information to local users, placing your
information in local files is also an option. This means that there
would be no off-machine access.
CERN's server is available for anonymous FTP from info.cern.ch
and many other places. Use archie to search for "www" or
"WWW" to find copies close to you. NCSA have their own
server, for FTP from ftp.ncsa.uiuc.edu.
See http://info.cern.ch/hypertext/WWW/Daemon/Overview.html
for more information on writing gateways and for servers in
general.
To produce HTML, you can either use an SGML editor with the
HTML DTD (URL is
http://info.cern.ch/hypertext/WWW/MarkUp/DTDHeading.html),
or use EMACS and html-mode.el (URL is
ftp://ftp.ncsa.uiuc.edu/Web/elisp/html-mode.el).
7. 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.
The principal difference between the three systems, it turns out, is
deployment. WWW does not have as large a user base as gopher,
mainly because of the small number of WWW browsers that are
out. This is changing as WWW reaches critical mass (usage of the
server at CERN doubles every 4 months -- twice the rate of
Internet expansion).
8. What is on the web?
**********************
Currently accessible through the web:
o anything served through gopher
o anything served through WAIS
o anything on an FTP site
o anything on Usenet
o anything accessible through telnet
o anything in hytelnet
o anything in hyper-g
o anything in techinfo
o anything in texinfo
o anything in the form of man pages
o sundry hypertext documents
One of the few limitations of the current networked information
systems is that there is no simple way to find out what has
changed, what is new, or even what is out there. As a result, a
definitive list of the web's contents is impossible at this moment.
There are, however, several resources which provide a great deal
of information on new and established servers by topic. These are
just two:
o The WWW Virtual Library at the URL
http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html,
a good place to find resources on a particular subject
o What's New With NCSA Mosaic at the URL
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html,
which carries announcements of new servers on the web
9. 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!
Credits
*******
o Thomas Boutell bou...@netcom.com
o Nathan Torkington Nathan.T...@vuw.ac.nz
o Marc Andreessen ma...@ncsa.uiuc.edu
o Tony Johnson
--
bou...@netcom.com, purveyor of fine HTML pages to the biology trade.
<a=href "http://siva.cshl.org/boutell.html">Click <em>here</em></A>