Some of the reference documents mentioned in this FAQ have also been included with the httpd documentation set. Since all of these documents are "living documents", you should fetch the latest versions from the net using the links here in the FAQ.
Robert B. Denny <rdenny@netcom.com>...?
This informational document is posted to news.answers, comp.infosystems.www, 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 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.
For information on FTP, send e-mail to
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In all cases, regard this document as out of date.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. Please excuse any formatting inconsistencies in the posted version of this document, as it is automatically generated from the on-line version.
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.
URLs look like this:
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).
In this document, you will often see URLs surrounded by angle brackets. This is done because some newsreaders (I am told) can recognize them and treat them as "buttons". Do not enter the angle brackets when entering a URL by hand to your web browser.
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.
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, 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 Unix (or VMS, or...) system you call, or telnet to a browser if you cannot do so.
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, 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 Unix (or VMS, or...) system you call, or telnet to a browser if you cannot do so.
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, 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 Unix (or VMS, or...) system you call, or telnet to a browser if you cannot do so.
Note: NeXT systems can also run Xwindows-based browsers using one of the widely used X server products for the NeXT. The browsers listed here, by contrast, are native NeXTStep applications.
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.
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.
See <http://info.cern.ch/hypertext/WWW/Daemon/Overview.html> for more information on writing servers and gateways in general.
A beginner's guide to HTML is available at the URL <http://www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimer.html>.
There is also an HTML primer by Nathan Torkington at the URL <http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-html.html>.
Fans of the EMACS editor can use EMACS and ).
There is also another Emacs HTML mode, html-mode.el (URL is <ftp://ftp.ncsa.uiuc.edu/Web/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.
For Xwindows users, TkWWW (listed above under XWindows browsers) supports WYSIWYG HTML editing; and since it's a browser, you can try out links immediately after creating them.
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.
NCSA's List of Filters and Editors, for which the URL is <http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/faq-software.html#editors>, mentions several editors, including two for MS Windows.
Note that this URL contains uppercase and lowercase letters; certain BROKEN browsers (apparently including Lynx for VMS) will require that you open it directly, entering the URL in quotation marks.
Another option, if you have an SGML editor, is to use it with the HTML
DTD
Rich Brandwein and Mike Sendall's List at CERN. The URL is
<http://info.cern.ch/hypertext/WWW/Tools/Filters.html>.
Note that this
URL contains uppercase and lowercase letters; certain
BROKEN browsers (apparently including Lynx for VMS)
will require that you open it directly, entering the URL in quotation marks.
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.
Gopher and World Wide Web usage are now running neck and neck,
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.)
This is changing as WWW reaches critical mass (usage of the server at
CERN doubles every 4 months -- twice the rate of Internet expansion).
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:
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!
Later you may return to this FAQ for answers to some of the
advanced questions covered in the second section. The advanced
section contains the most-asked technical questions in the group.
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>.
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>.
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:
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:
(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.
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.
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.
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.
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.
However, there is a way to use HTML+ 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+ and outputs
html using the 3.4.2.3: 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:
3.4.3: How do I publicize my work?
There are several things you can do to publicize your new HTML server
or other offering:
3.5: 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.3.6: What is on the web?
Currently accessible through the web:
3.7: I want to know more
4: Advanced Questions
4.1: How do I set up a clickable image map?
4.2: How do I make a "link" that doesn't load a new page?
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/1.0 204 No response
Server: Myscript/NCSA httpd 1.1
4.3: Where can I learn how to create fill-out forms?
You can read about the Common Gateway Interface
at the URL
<http://hoohoo.ncsa.uiuc.edu:80/cgi/>. In addition to documenting
the standard interface for which scripts can now be written for
both NCSA and CERN-derived servers, these pages also cover
HTML forms and how to handle the results on the server side.
4.4: How can I save an inline image to disk?
4.5: How can I get sound from the PC speaker with WinMosaic?
4.6: How do I comment an HTML document?
4.7: How can I create decent-looking tables and stop using
Tables are a standard feature in HTML+, a forthcoming superset of
HTML. Unfortunately, they are at present implemented only
by the Viola and Emacs-W3
browsers, to my knowledge.
...
?...
construct to represent tables,
allowing you to write HTML+ now, knowing that it will look
better when clients are ready for it.
5: Credits