CompuServe CB was the first public, commercial
multi-user chat program. It first went live on February 21, 1980, built to
over a million subscribers by 1988, and was CompuServe's most popular service
through their acquisition by AOL in 1997.
In the middle of the start of the beginning of a series of
technological revolutions -- from 1985 through 1995 -- CompuServe provided
the common virtual space for technical support for high-tech companies from
Adobe
to IBM to Lotus to Microsoft. Each company had one or more CompuServe "Forums" which
included a number of virtual "conference rooms" for visitors to chat, all supported
by the CB technology.
Because of its ubiquitous use in the technical community,
CompuServe CB was widely influential on chatting culture, and many of the common
abbreviations used on the Internet, such as IMHO, MORF, and textual
emoticons like ;) first came into common online use on CB.
Architecturally, the original CB application was based on
a Macro-10 program using features of CompuServe’s proprietary PDP-10 operating
system, in particular shared read/write memory segments. The original author
was Sandy
Trevor, a V.P. at the time, who eventually “wrote
it in assembly language over a weekend on my kitchen table.” The very simple
architecture enabled the system to support the kinds of high-demand interactivity
that chat requires; for example, CB was able
to support
over
300
simultaneous
users on a 1 mips DEC KI-10, six times more users than typical at that time.
For universality of access, only the simplest of ASCII terminals
was needed to use CB, but of course by late 1989 innovation had reared its
creative head and more sophisticated CB clients were developed that included
separate windows for sending and receiving, similar to today’s instant messaging
clients.

Early implementations of CB included
encrypted communications and enhancements to support multi-user games. The
first recorded online
wedding was performed on CB in 1983. By
1995, CompuServe CB supported multimedia, which “got rolling” with Mick Jagger’s
historic online conference from London on December 7, 1995.
Resources. The following references provide
more information:
- Bowen, Charles; How to Get the Most Out of CompuServe; 1982
- Want, Wallace; Wang, Wally; CompuServe for Dummies; 1996.