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You will likely first experience the World Wide Web through a WWW
client. In WWW terms, these are called browsers. Browsers are
available for almost all major computer platforms, however you also
need the appropriate network infrastructure to make them work.
- Network Infrastructure
What browser you use depends largely on how you are connected to the
Internet. If you are using a terminal emulator and a serial
connection, you will most likely use a character-mode browser. If you
can send network packets from your computer to the Internet, you will
probably use a graphical-mode browser.
- Character-Mode Browsers
A popular character-mode browser is Lynx.
You cannot use Lynx to display graphical images, but it does support
forms, as well as all HTML 2.0.
- Graphical Browsers
Three popular graphical browsers are Mosaic , Netscape and Microsoft Internet
Mosaic and Netscape are available for Microsoft Windows, X-Windows,
and the Macintosh, while Microsoft's IE is only available for
Microsoft Windows. Mosaic and Microsoft IE are free to anyone;
Netscape is free to any not-for-profit institution.
How you connect to the Internet affects how you view the WWW. If you
connect via a modem, you won't be able to view large WWW pages,
images, sounds, or video; if you have a T1 connection (1.544M
bits/second), you will be able to enjoy these features. Some WWW
pages assume that you have a fast connection to the Internet.
Local Area Networks
If your Local Area Network has a gateway to the Internet (there are
several different methods to do this), you should be able to use a
graphical browser on your own workstation to cruise the WWW. If you
are using a PC with Microsoft Windows, you'll need to have a
Winsock interface installed (in addition to the regular networking
configuration). Macintosh users already have network support via
MacTCP. UNIX workstation users should also have built-in support for
There are two methods of dialing into a machine to get access to the
Internet. If you dial in and log on as usual (on UNIX you see
"login:" and shell prompt or on MPE you type "HELLO" and get a colon
prompt), your computer is not directly connected to the Internet, so
it cannot send network packets from your PC to the Internet. In this
case, you will have to use Lynx to access the WWW.
If you dial-in using SLIP (Serial Line IP) or PPP (Point-to-Point
Protocol), your computer becomes part of the Internet, which means it
can send network packets to and from the Internet. In this case, you
can use graphical browsers like Mosaic or Netscape to access the WWW.
Adapter is supposed to allow users with only shell account access
to obtain a SLIP connection.
Shiva and Livingston
provide products that allow users to dial into hosts using SLIP or
While Lynx is not the only character-mode browser, it is one of the
most powerful. Lynx
is available for many platforms. You can obtain a pre-compiled
version of Lynx for MPE/iX from
Some users are disappointed that Lynx's display is limited to text.
What Lynx does demonstrate is that a single server can provide
information to both character-mode and graphical clients. Still, to
gain a full understanding of how powerful the client/server concept
can be, you should compare Lynx's capabilities to the capabilities of
graphical browsers such as Mosaic or Netscape.
Mosaic is one of the tools that makes the WWW so popular. With
Mosaic, you can view in-line graphical images surrounded by
proportional font text in multiple colors. For an excellent
introduction to Mosaic, see the O'Reilly book The Mosaic Handbook. Three versions of
the book are available (Windows, Macintosh, and X-Windows). The PC
version of Mosaic requires the Win32s subsystem which is described in
Mosaic readme file.
While Mosaic is popular, the newer Netscape browser is even more
appealing, especially when used with slower network connections.
Earlier versions of Mosaic did not display anything until an entire
URL (and its associated graphical images) had been downloaded.
Netscape, by contrast, starts displaying as soon as a screenful of
information is available. As you page down through a document,
Netscape barely pauses as it continues to download the URL in the
The newest graphical browser is the Microsoft Internet
Explorer. This browser is part of Microsoft's strategy to make the
Internet an important part of all Microsoft products. Like Netscape,
the Microsoft IE also does background network transfers. We perfer
Netscape over Microsoft IE, due to Netscape's user interface and
Neither Mosaic nor Netscape tries to handle all the data that can
potentially be served up on the Web. They both understand HTML,
in-line graphics, and URLs. Netscape can display external GIF
(Graphics Interchange Format) files, but Mosaic cannot. To view
images, listen to sound, watch movies, or view spread sheets, you must
external tools to support these data formats. For Microsoft
Windows users, a popular graphical viewer is LView.
The Mosaic Handbook provides a good introduction to the external tools
that you need to support full multimedia applications. Most of these
tools also work with Netscape.