Notice: This material is excerpted from Special Edition Using HTML, 2nd Edition, ISBN: 0-7897-0758-6. This material has not yet been through the final proof reading stage that it will pass through before being published in printed form. Some errors may exist here that will be corrected before the book is published. This material is provided "as is" without any warranty of any kind.
by Mark Brown
They say that the camera never lies. A photograph is a record of a real
scene as it was captured by the camera's lens.
On the other hand, two artists never paint the same scene the same way. Every element is subject to the artist's interpretation. One artist might paint a photo-realistic image that's almost sharper than reality; another might render an abstract smear that communicates mood more accurately than it portrays the scene. They might move, add, remove, or alter objects or change lighting to suit their depictions of the scene.
The World Wide Web works more like painting than it does like taking
photographs. A
Web server "serves up" a page over the
Internet,
and a
Web browser program interprets it. The results may be almost as different
as the two painting styles described above. This is the central, surprising
truth about the World Wide Web: what you see on a Web page is described,
not defined, by its HTML code. It is up to the user's browser program
to render it in its final form.
Many new Web developers are shocked to discover that they have so little control over the final appearance of their pages. But, for better or worse, that's how the Web works. If you want to create Web pages that can be viewed accurately by a wide range of WWW users, you're going to have to be aware of the different server and browser programs that are out there and how they work together.
The World Wide Web has a
client/server architecture. This means
that a client program running on your computer (your Web browser) requests
information from a server program running on another computer somewhere
on the Internet. That server then sends the requested data back over the
Net to your browser program, which interprets and displays the data on
your screen. Figure 2.1 shows the whole
process graphically. The following steps explain the process:
This is what happens when you view a page on the World Wide Web.
Many
computer networks include a
security mechanism called a
firewall. A firewall is software (often combined with specialized hardware) that creates a barrier to keep unauthorized outside users from accessing a site. If a system is equipped with a firewall, inside users must use proxy programs to access the
Internet. Although this adds a couple of steps, the fundamental process of transferring data back and forth between client and server is essentially unchanged.
You can also set up a server to run a Web site over a LAN (local area network) without connecting it to the outside world at all. This is sometimes referred to as an Intranet. In this scenario, only those connected directly to the LAN are able to access the pages on the server. Many companies use a setup like this for distributing internal information to their employees.
To browse the Web, you need a client computer. There are two basic requirements
for this machine: it must have a connection to the Internet and must be
capable of running a
Web browser program.
The Internet connection can be hard-wired, or it can be a dial-up phone
connection via modem to an Internet service provider (ISP). You're most
likely to have the former at work or school and the latter at home. The
only difference you will notice between the two is speed; otherwise, they
work identically.
There are Web browser programs for just about any computer you can name, from dumb text-only terminals running on mainframes to off-brand personal computers, such as the Amiga. (I'll list and discuss the most popular browser programs later in this chapter.)
On the content-provider side of things, you need a server computer. This machine has requirements similar to those of the client computer: it must be connected to the Internet and must be able to run a Web server program.
A
Web server program is often called an HTTPD, for
HyperText Transfer Protocol Daemon. Daemon is computerese for a program that runs unseen in the background.
However, a Web server needs a more robust
Internet connection than a
Web client does. A server should ideally be hooked up to the
Internet via
a fast dedicated T1 or T3 line that remains connected all the time. Otherwise,
people trying to access your Web site will often find that it just isn't
there.
It is possible (though excruciatingly slow) to run a Web site on a dial-up line, especially if you can find an Internet service provider who will let you stay dialed in 24 hours a day without disconnecting you. However, you must make sure that your ISP can assign a permanent IP address to your machine-not a new IP address each time you connect. Otherwise, people won't even be able to find your site.
A good intermediate solution to the direct vs. dial-up problem is an ISDN line. A sort of super fast digital phone line, an
ISDN line costs more than a regular phone line but much, much less than a dedicated T1 or T3 line. It also requires a special interface card for your computer.
ISDN lines are offered by most phone companies in
urban areas and
university towns, but you'll need to find an ISP that can provide an ISDN connection too. Contact the business office of your local phone company for details.
HTTPD server software is available for a wide variety of computers (see
fig. 2.2). Surprisingly, server computers don't have to be very powerful;
serving up Web content is simply not that demanding. More of a concern
is having a multithreaded, multitasking operating system so that the server
can handle several tasks at once without bogging down. Storage is a concern,
however, because Web sites are notorious for growing without limit.
The Spry Web Server for
UNIX X Windows has a rich
GUI for configuration
and
maintenance tasks.
An HTTP connection is said to be stateless. That is, no permanent
connection is maintained between the server and the client. A request is
made, and the connection is broken. Then a response is sent back, and the
connection is broken again. This process is repeated for every request
and often even for parts of a request. Programmers refer to this as a query-response
model of interaction. It's the reason your browser program always seems
to be saying "Waiting for reply..." in its status display line.
(See the message at the bottom of fig. 2.3.)
A browser's request for information takes the form of a URL (Uniform Resource Locator), which is also referred to as a page's address or location. URLs almost always look something like this:
http://www.somesite.net/path/webpage.html
A URL is always a single, unbroken line of text with no spaces.
Web browsers generally display the
URL of the Web page currently being
viewed near the top of the window (see fig.
2.3).
Web browsers let you know where you are on the Web by displaying
the page's URL. Netscape shows this near the top of the display window
and labels it "Location."
Here's a real world example of a URL, taken from figure 2.3:
http://www.microsoft.com/msoffice/freestuf/msword/download/ia/default.htm
The "http://" portion of the URL indicates that the browser
has requested a transfer via HTTP protocol; that is, it wants a Web page.
"www.microsoft.com" is the domain name of the server being queried;
in this case, it's the Web server at Microsoft. The "
msoffice/freestuf/msword/download/ia/"
portion of the URL is the path name on the server's hard drive for the
file you want. (Fortunately, this example is of one of the longer path
names you're likely to run into on the Web.) "default.
htm" is
the name of the actual
HTML file on the server; it's what is being displayed
on the screen in figure 2.3.
See "Domain Names"
If the protocol portion of a URL is
https:// or snews://, it means that the connection is secure. In Netscape, this will be confirmed by the presence of an unbroken security key in the lower left-hand corner of the screen.
URLs can reference not only Web pages, but just about any service on
the Internet, including FTP, Gopher, WAIS, Usenet, and Telnet. You can
even load in a file from your own computer! Table 2.1 shows the syntax
for the various types of sites that can be accessed via a
Web browser.
Table 2.1 URL Syntax for Addressing Various Types of Internet Sites
URL Syntax | Type of Access |
---|---|
file:// | a file on your local computer |
ftp:// | an FTP server |
gopher:// | a Gopher server |
http:// | a Web page |
news:// | a Usenet newsgroup |
telnet:// | a connection to a Telnet site |
WAIS:// | a WAIS server |
See "Linking HTML Documents"
The domain name portion of a URL may include a colon followed by a port
number, like this:
http://www.somesite.net:80/path/webpage.htm
This tells the server to access the site via a specific assigned port.
Port 80 is the default port defined in the
HTTP specification. If not given, it is assumed.
Web page file names usually end in .htm or .html to indicate that they
are HTML content files. Many home pages don't have path names or file names
at all. Their URLs are in a very abbreviated format:
http://www.somesite.net
These addresses access a page that is stored in the server's root directory; that is, they don't need a path name because they aren't stored in a subdirectory. Most servers also assume a default file name for the home page, such as hompage.html or index.htm. If no page file name is specified, the server will automatically serve up the default page.
URLs can point to other types of files than HTML Web pages, of course.
For example, the URL http://www.somesite.net/logo.
gif would display a
GIF
image file. http://www.somesite.net/path/program.zip would, depending on
how your browser is configured, prompt you to save the specified
ZIP file
to disk or would decompress the file and store the resulting program files
to disk.
Sometimes you may see a URL that looks something like this:
http://www.somesite.net/cgi-bin/findit&toad+frog
Servers can include gateways, which enable them to run application
programs called CGI (Common Gateway Interface) scripts or programs.
These are, in most ways, just like any other programs run by a computer.
Depending on the machine and the gateway, CGI-bin (bin for binary)
programs might be written in C, C++, BASIC, or the PERL scripting language.
A URL like the one above instructs the server to run the CGI program called
findit using the data toad and
frog as inputs. In this example, it would
be a fair guess that the server program, findit, was some sort of indexing
program and that the user had instructed it to find references in its database
to toads and
frogs.
See "All About CGI" See "Sample Code and CGI Scripts"
Some hyperlinks may reference a relative URL; that is, one in the same path name on the same server as the page currently being viewed. For example, if the current page is http:// www.somesite.net/path/thispage.html, a relative link to thatpage.html would load in the page whose absolute address is http://www.somesite.net/path/thatpage.html. This technique not only saves page creation time and space on the server, but it makes it very easy to move all of the files associated with a Web site to a new directory or even to a new machine. Only the references to the home page need to be changed; relative URLs remain the same.
A Web server computer runs an HTTPD (HyperText Transfer Protocol Daemon)
program (see fig. 2.4). The history behind
the development of HTTP is told in Chapter 1, "Overview
of the Web." This section will concentrate on how Web servers
use HTTP to communicate with browser clients.
NetPublisher is an HTTPD server program for
Windows NT. Unlike many
bare-bones UNIX servers, NetPublisher sports an intuitive
GUI.
When you analyze what a server does, you begin to fully realize just how much of the look and feel of the World Wide Web is in the browser program.
The browser client strips a URL down to its component parts: protocol, address, path name, and file name. From the protocol portion, it determines how it is going to interact with the server that it's addressing and how to display the data it will receive. It then calls the address contained in the URL and waits for a response from the server.
Once the server realizes that a request is coming through, it likewise checks the URL for the connection protocol (e.g., http:// for a Web page). It takes the path name and file name that it has been given, finds them on its hard drive, and sends the data off to the browser using the correct protocol.
Then it's the browser's turn again. This time it gathers in, interprets, and properly displays the data it has received.
It probably seems like there is a lot more for the browser to do in this process than there is for the server, and in the case of a simple transaction, such as viewing a Web page, that's probably true. But there's much more than that going on in the background.
For example, if there's an error somewhere along the way-such as, a
request for a page that doesn't exist-the server has to send back the proper
error message. If the user has requested an action that requires running
a CGI program, the server has to load and run the program. This process
usually means creating a custom HTML page "on the fly" that contains
the results of the program's action, then sending that back to the browser.
Then, too, every data file transmitted by the server has to be properly
identified by type and tagged with the appropriate MIME (Multipurpose
Internet Mail Extension) data type header so the browser will know what
to do with it. Most
Web pages include a mix of
HTML formatted text, GIF
and
JPEG graphics, and maybe even audio and
video clips; each must be properly
tagged, or the browser won't know how to interpret the pieces when they
arrive.
See Chapter 1, "Introducing the World Wide Web"
Today's Web servers also include all kinds of esoterica-for example,
data
encryption and client authentication. These take up a great deal of
the server's time, too.
Factor in the fact that a server is often handling requests from hundreds of clients at any one time, and you'll see that there's more than enough going on to keep it busy.
For more information on servers, check out the Usenet newsgroups comp.infosystems.www.servers.misc, .mac, .ms-windows, and .unix.
The HyperText Transfer Protocol (HTTP) was designed to be quick, simple,
and nonintrusive. The connection between a server and a client program
(or agent) is temporary and must be reestablished for every data
transfer.
The HTTP specification incorporates a whole set of methods that are
used to perform the tasks associated with servicing a
Web site, including
information retrieval, searching, front-end updating, and annotation. The
specification is open-ended, so additional functionality can be added without
making the whole Web obsolete.
As discussed previously, messages are passed in a format that is similar
to Internet Mail and the
Multipurpose Internet Mail Extensions (MIME);
gateways enable browsers to request the
execution of CGI applications on
the server hardware; and communication is possible with other
Internet
protocols, such as SMTP, NNTP, FTP, Gopher, and WAIS.
HTTP is, like these earlier protocols, a TCP/IP protocol. However, it can be implemented on top of any other protocol implementation that can communicate over the Internet or on other networks, including LANs.
The current version of the
HTTP protocol specification can be found at the site
maintained by the HTTP Working Group at http://www.ics.uci.edu/pub/ietf/http/.
Almost any computer platform that you can name (and some you probably
can't) can act as a Web server. There are HTTPD server programs for systems
as varied as
multimillion-dollar mainframes and
PCs costing under $1000.
Which one is best? That's a question that is highly subjective, and it's certainly beyond the scope of this book. A more important question might be, "Do I need an HTTPD server program at all?"
If you usually hook up to the Web through an Internet service provider
(ISP) and are thinking about setting up a personal
Web site, the answer
is almost certainly no! What you need is an account on somebody
else's Web server, probably that of your ISP. Most ISPs offer a place for
your own home page for little or nothing if you're already using their
dial-up services. For example, my local ISP charges me $30 a month for
unlimited
Internet access and includes a 10 megabyte
UNIX account on which
I can keep my own
World Wide Web pages.
If you think about it, this is an incredible bargain. For $1 a day-which is less than I pay for cable TV-I maintain a Web site that can be seen by anyone in the world, 24 hours a day! And they take care of all the headaches of setting up and configuring the server, maintaining the site, and handling glitches and bugs. It's great. All I have to do is develop the content for my site, write it in HTML, and upload it to my provider.
For an example of what kind of site you can set up using somebody else's Web server, check out my personal Web site at http://www2.giant.net/people/mbrown.
Even small to medium sized companies might want to consider having an
ISP host their sites rather than setting up their own
Web server. It can
mean a major investment of both time and money to set up a server computer,
hook it up via a permanent T1 or T3 land line, install the HTTPD software,
and maintain all of that hardware and software over time. If your needs
are moderate, having an ISP take care of all that for you can be a major
headache reliever.
You can find a searchable list of
Internet service providers on the
ISP Yellow Pages site at http://www.index.org/.
However, if you are developing Web pages for a college or major corporation, you'll probably want to run your own site. This is the best way to go if your site:
If any of these criteria describe the site you want to set up, then pick a computer platform and HTTPD server software that match your requirements.
It is beyond the scope of this book to review all of the many HTTPD servers that are currently available; nonetheless, I can discuss the ones that are the most popular. Although popularity is not exclusively determined by quality-price and compatibility are certainly major issues as well-it can serve as a good measure of which server programs are already working for a large number of sites.
The server use statistics in this section were taken from the server survey data at http://www.mirai.com/survey and from the Spry Webcrawler statistics at http://www.webcrawler.com/WebCrawler/Facts/WebFacts.html.
Accurate statistical data about Web server usage is hard to come by.
Most is based on random samplings of sites or on volunteer surveys,
which can be highly skewed by inaccurate survey samples. But a comparison
of the best data currently available on the Web seems to lead to the following
conclusions about which computer platforms are probably the most popular
Web servers:
This breakdown is shown graphically in the pie chart in figure 2.5.
Sun workstations,
personal computers, and
UNIX systems split the
server market into near-equal thirds.
A little over a year ago, more than 80 percent of the servers on the
Web were UNIX-based. The shift shown in figure 2.5 certainly reflects two
current trends: The rapid growth of the World Wide Web has moved it beyond
the confines of academia and corporate America, where UNIX is most popular,
and there has been, in the last year, a proliferation of HTTPD software
for platforms other than UNIX.
Let's take a look at specific servers.
One of the major reasons for UNIX's predominance has been the number of freely distributable HTTPD server programs available for it. CERN HTTPD and NCSA HTTPD have historically been the two most popular server programs on the Web, and they remain at or near the top of the list.
However, a plethora of new server programs has been introduced in the
past year, and some of them are gaining market share quickly. Although
there are a few new freebies-Apache, for instance-many of the fastest-growing
servers are commercial packages from such companies as Netscape, Quarterdeck,
and Open Market.
There are many good reasons for the fast growth of commercial Web server programs. For the price, those buying commercial servers get the peace of mind that comes with knowing that the product is fully supported, not freeware with a nebulous cloud of hobbyist developers working on it in their spare time. Then, too, these products are finished goods; they don't need to be compiled to run and are packaged with complete documentation and a full set of additional Web development software tools.
Further, commercial servers usually offer additional functionality that
just isn't found in
freeware servers, such as encryption and security.
And finally, most of the current growth of the Web can be directly attributed
to the addition of many new
commercial sites. Unlike the personal and academic
sites that preceded them, commercial sites aren't scared off by the $400-$5000
price tag that commercial server software carries.
Table 2.2 lists the most popular servers on the Web, as nearly as can be determined by current data. Figure 2.6 shows the same data graphically.
Table 2.2 The Most Popular HTTPD Server Software
Server |
Availability | Platform(s) | Pct |
---|---|---|---|
NCSA | Free | UNIX/Win | 41 |
Apache | Free | UNIX | 17 |
Netscape | Commercial | UNIX/WinNT | 13 |
CERN HTTPD | Free | UNIX | 11 |
WebSTAR/MacHTTP | Comm/Free | Macintosh | 17 |
Others | Comm/Free | Varied | 1 |
Source: Web Servers Survey Version 2.0, January 1996, by Paul E. Hoffman, Proper Publishing, http://www.proper.com/.
Many of the most popular Web server software in use today are
freeware,
but commercial servers are gaining ground.
There are, of course, a great many more HTTPD server programs available
than those shown in Table 2.2. Table 2.3 lists HTTPD server programs for
a variety of platforms. To find out more about any of these servers, check
out Paul Hoffman's Server Comparison Chart on the
Web. This site contains
a wealth of data for anyone who is thinking about establishing a presence
on the
World Wide Web, including
hypertext links to the
publishers of most
of the Web server programs listed in
Table 2.3. Its location is http://www.proper.com/www/servers-chart.html.
Table 2.3 HTTPD Server Programs by Platform
Platform |
Server |
Amiga | Amiga Web Server |
AS/400 | Server/400 |
Macintosh | CL-HTTP, FTPd, httpd4Mac, MacHTTP, WebSTAR |
Novell | SiteBuilder, Webware |
OS/2 | GoServe |
UNIX | Apache, Boa, CERN, CL-HTTP, GN, NaviServer, NCSA, Netscape Commerce, Netscape Communications, Open Market Secure WS, Open Market WebServer, Phttpd, SafetyWEB UNIX, Spinner, Spry Web UNIX, TEAMate, WN |
VM/CMS | Webshare |
VMS | CERN, Purveyor, Region 6 |
Windows 3.1 | FrontPage, Quarterdeck |
Windows 95 | Alibaba, Commerce Builder, Communications Builder, FolkWeb, FrontPage, Purveyor, Quarterdeck WebServer, SAIC, WebQuest, WebSite |
Windows NT | Alibaba, Commerce Builder, Communications Builder, FolkWeb, FrontPage, HTTPS, Microsoft's Internet Information Server, NaviServer, NetPublisher, Netscape Commerce, Netscape Communications, Purveyor, Quarterdeck, SafetyWEB NT, SAIC, Spry Web NT, WebQuest, WebSite |
To a large degree, the Web is what your Web browser makes it. Because
Web pages are written in
HTML and because
HTML is subject to interpretation,
your browser profoundly affects the appearance of
Web pages and, consequently,
your impression of the
World Wide Web as a whole.
Figure 2.7 shows the same Web page as
viewed by three different browser programs: the all-text UNIX Lynx browser
(upper left), an older
Windows browser called Cello (upper right), and
Netscape Navigator 2.0 (lower right). The fourth image (lower left) is
the same page displayed by
Netscape 2.0 with customized color and
font
settings. You can see how differently various browsers can interpret the
same page and how significant user settings are in the outcome.
The same Web page can be displayed in very different ways by different
browser programs.
That's why it's important to make sure you have a good browser program (see fig. 2.8) if you're going to develop HTML documents for the World Wide Web. You want to make sure that your viewers are seeing the same pages you are.
Netscape Navigator, shown here in version 2.0 for Windows 95, is
the most popular browser program in use on the Web today. In this screen
shot, Netscape displays a 3-D VRML (Virtual Reality Modeling Language)
virtual world using the WebFX plug-in.
As a sort of experiment, you can simulate a Web browser program by Telneting into a Web site and executing the same command by hand that a browser would. Perform the following steps:
For more information on Web browser programs, check out the Usenet newsgroups comp.infosystems.www.browsers.misc, .mac, .ms-windows, and .X.
HTML is not intended to be an all-encompassing, all-powerful page layout
environment.
HTML describes a page's look by using markup tags to indicate
the relative position of elements on the page. For example, you can specify
which lines of text are headings and their level of importance. You can
show where in the text an in-line image should appear and whether certain
blocks of text should appear with a particular type of formatting. You
can even create tables and forms. With some of the most recent versions
of HTML, you can create frames in which different parts of pages are displayed,
put up
graphic background wallpaper, and change the color of text
on the fly.
See "Netscape-Specific Extensions to HTML"
See "Additional HTML Extensions Supported by Other Browsers"
HTML cannot, however, determine which font,
font size, or color will
be used to display text; what the screen background color will be; how
the colors in
graphics will be interpreted; or any of a wide variety of
other variables that are at the mercy of browser programs or the users'
settings of various options in their browser programs.
"Why doesn't HTML give a page
creator more control?" you ask.
HTML's main appeal is that it is easy to learn and easy to use. Ease
of implementation was, in fact, the major design criterion for HTML, and
it worked. A recent survey of Web page creators found that over half of
them learned the basics of HTML in under three hours, and another quarter
took only six hours. Most said that a good book (like this one!) and the
Web itself were the only tools they needed to begin creating Web pages.
HTML was also designed to be compatible across a wide range of machines,
from text-only
UNIX terminals to the flashiest
Silicon Graphics workstation.
To a large degree, that goal has been met, too. Although there will certainly
be some differences in the same
Web page viewed on different machines with
different browsers, the results will likely be similar enough and acceptable
enough to convey the information presented in the manner intended by the
page's creator.
The responsibility for making sure this happens rests squarely on the
shoulders of the Web developer-you! Properly applied, HTML can make your
pages look good on a wide variety of platforms. The more aware you are
of the differences in Web browsers, the better you'll be able to make sure
your pages look good on all (or at least most) of them.
See "Accommodating WWW Users and Their Viewers"
If you really want the pages you put on the Web to retain their original look and feel, you might want to consider making them available as PDF (Portable Document Format) files. A lot of companies and organizations do, from Adobe Systems to the IRS.
A
PDF file can't be read by a
Web browser though-it needs an external viewer program.
Adobe Acrobat is the most popular
PDF format on the Web today. You can get information about Acrobat (and download a free viewer) from the Adobe Web site at http://www.adobe.com.
So which Web browser clients are the most popular? That's one with an
easy answer. The most popular Web browser today is
Netscape Navigator,
which is used by over 80 percent of those cruising the Web. Other browsers
don't account for over four percent of the market each.
Does this mean that you can, with impunity, develop only for Netscape
and ignore the rest? In a word, no. First of all, there are several different
versions of Netscape Navigator out there, running on UNIX, Windows, Windows
95, and Macintosh platforms. If you want to use some of the latest and
greatest Netscape features-such as frames -you'll leave behind the three-quarters
or more of your Netscape audience who are, as of this writing, still using
Netscape 1.1. (See Chapter 15, "Netscape-Specific
Extensions to HTML.") And the 20 percent of Web users who don't
use Netscape Navigator are a sizable chunk of your audience too. You don't
want to leave them out in the cold, do you?
Table 2.4 should give you some idea of the wide variety of client programs that are out there browsing the Web.
Table 2.4 Web Browser Programs for
Various Platforms
Platform | Browser | Comments | |
---|---|---|---|
AMIGA | Amosaic | Based on NCSA Mosaic. FTP from aminet sites in /pub/aminet/comm/net. Homepage at http://insti.physics.sunysb.edu/AMosaic/home.html. FAQ at http://www.phone.net/ATCPFAQ/amosaic.html. | |
Amiga Lynx | Home page at http://www.fhi-berlin.mpg.de/amiga/alynx.html. | ||
EMACS w3-mode | Multi-platform browser for EMACS editor. Runs under Gnu EMACS on the Amiga. FTP from ftp.cs.indiana.edu/pub/elisp/w3. | ||
![]() |
Enhanced Mosaic | From Spyglass. Multi-platform. Commercial version of NCSA Mosaic. Can only be licensed by OEMs. Home page at http://www.spyglass.com. | |
MacWeb | Available only as part of TradeVPI. See http://galaxy.einet.net/EINet/MacWeb/MacWebHome.html | ||
NCSA Mosaic | Multi-platform and still free (see fig. 2.9). FTP from ftp.ncsa.uiuc.edu/Mac/Mosaic. | ||
Netscape Navigator | Tables, HTML extensions. Free to nonprofit and educational institutions; free 90-day evaluation for individuals. Home page at http://home.netscape.com/comprod/products/navigator/. FTP from ftp.netscape.com. | ||
MS/DOS | DOSLynx | Can view GIFs, but not in-line. FTP from ftp2.cc.ukans.edu/pub/WWW/DosLynx. | |
Minuet | Both text-mode and graphics-mode display. FTP from minuet.micro.umn.edu/pub/minuet/latest/minuarc.exe. | ||
NEXTSTEP | CERN | Out of date; editor not operational. | |
![]() |
Requires NeXTStep 3.0. FTP from ftp.w3.org/pub/nextapp. | ||
EMACS w3-mode | (see Amiga listing) | ||
Netsurfer | FTP from ftp://ftp.netsurfer.com/pub/Netsurfer/ Home page at http://www.netsurfer.com. | ||
OmniWeb | Home page at http://www.omnigroup.com/ FTP from ftp://next-ftp.peak.org/pub/next/binaries/wide-area-info/ | ||
Spider Woman | Multithreaded, graphical. FTP from sente.epfl.ch/pub/software. Home page at http://sente.epfl.ch/. | ||
TEXT-MODE | EMACS w3-mode | (see Amiga listing) | |
UNIX/VMS | Line Mode Browser | For dumb terminals. FTP from ftp.w3.org/pub/linemode. | |
Lynx | For VT100. FTP from ftp2.cc.ukans.edu. | ||
PERLWWW | By Tom Fine. TTY-based, written in PERL. FTP from archive.cis.ohio-state.edu/pub/w3browser/w3browser-0.1.shar. | ||
VMS | By Dudu Rashty. FTP from vms.huji.ac.il/www/vms_client. | ||
VM/CMS | Albert | FTP from ftp.nerdc.ufl.edu/pub/vm/www/. | |
Charlotte | Written in REXX, runs on any CMS from v5 to v11. Gopher at gopher://p370.bcsc.gov.bc.ca. | ||
WINDOWS 3.1/NT/95 | Cello | From Cornell. Outdated. FTP from ftp.law.cornell.edu/pub/LII/cello | |
CompuServe Mosaic | From CompuServe. Comes with CompuServe subscription. | ||
EMACS w3-mode | (see Amiga listing) | ||
Emissary | From Wollongong. Home page at http://www.twg.com. | ||
Enhanced ![]() |
(See Macintosh listing) | ||
I-COMM | Operates without a ![]() |
||
Internet Explorer | From Microsoft (see fig. 2.10). Many HTML extensions. Home page at http://www.microsoft.com. | ||
Internet Works | Now a part of Global Network Navigator and America Online. For information, contact http://www.gnn.com. | ||
Netscape Navigator | (See Macintosh listing) | ||
NetShark | From InterCon Systems. Home page at http://netshark.inter.net. Supports HTML extensions. FTP Lite version from netshark.inter.net/pub/netshark/. | ||
Quarterdeck Mosaic | From Quarterdeck. HTML extensions. 30-day evaluation copy downloadable from http://www.qdeck.com/qdeck/demosoft/QMosaic. | ||
![]() |
Operates without SLIP or ![]() |
||
UdiWWW | Supports most of proposed HTML 3.0 plus Netscape extensions. Home page at http://www.uni-ulm.de/~richter/udiwww/index.htm. | ||
WinMosaic | From NCSA. FTP from ftp.ncsa.uiuc.edu/PC/Windows/Mosaic. Home page at http://www.w3.org/hypertext/WWW/MosaicForWindows/Status.html. | ||
WinWeb | Available only as part of TradeVPI. See http://galaxy.einet.net/EINet/WinWeb/WinWebHome.html | ||
IBM OS/2 | Web Explorer | Multithreaded with visual map of session. FTP from ftp01.ny.us.ibm.net/pub/WebExplorer. | |
WebSurfer | From Netmanage. Included with Chameleon TCP/IP software package. | ||
X/
DECWINDOWS |
Arena | Test bed for HTML Level 3. FTP from ftp.w3.org/pub/arena. | |
Chimera | Uses Athena (doesn't require Motif). FTP from ftp.cs.unlv.edu/pub/chimera. | ||
![]() |
(see Amiga listing) | ||
Enhanced Mosaic | (see Macintosh listing) | ||
MMM | Tcl/Tk user interface. Supports plug-in applets written
in ![]() |
||
NCSA Mosaic for VMS | (see Macintosh listing) | ||
NCSA Mosaic for
X |
(see Macintosh listing) | ||
Netscape Navigator | (see Macintosh listing) | ||
Quadralay Mosaic | From Quadralay. Commercial Mosaic for UNIX (Windows and Macintosh versions planned). Home page at http://www.quadralay.com/products/products.html#gwhis. | ||
TkWWW | UNIX Browser/Editor for X11. Supports WSYIWYG HTML editing. Home page at http://www.w3.org/hypertext/WWW/TkWWW/Status.html. | ||
Viola for X | Two versions: one using Motif, one using Xlib. HTML Level 3 forms and tables. FTP from ora.com/pub/www/viola. Home page at http://xcf.berkeley.edu/ht/projects/viola/README. |
NCSA Mosaic was the original
Web browser program. It has kept up
well and is still available for Macintosh, Windows 3.1, Windows NT, Windows
95 (shown here), and X Windows systems. Many other browsers are derived
from the original
NCSA Mosaic source code.
Microsoft's Internet Explorer (shown here in its v2.0 release for Windows 95) is one of the most recent and one of the most powerful Web browser programs currently available.
The information in this table came from the World Wide Web Frequently
Asked Questions (FAQ) list, which is maintained by
Thomas Boutell. You
can download the latest version at http://www.boutell.com/faq/
or http://www.shu.edu/about/WWWFaq/.
Batch-mode browsers retrieve the contents of a URL specified on the
UNIX shell command line and are intended for use in scripts. (Most of the text-based UNIX browsers can also do this.) One is available at ftp.cc.utexas.edu/pub/zippy/url_get.tar.Z. Another, written in extended Tcl (tclX), is available at http://hplyot.obspm.fr/~dl/wwwtools.html.
For technical support for our books and software contact support@mcp.com
Copyright ©1996, Que Corporation