Atari 400 User Manual page 215

has the most extensive catalog of programs for
Atari-brand home computers.
In fact, Atari markets many unique programs
through the Atari Program Exchange (APX).
These programs are created by Atari users and
are created internally by Atari, also. The APX dis-
tributes this user-written software by mail order
and through many Atari retailers. The APX holds
quarterly contests
to
pick the best programs de-
veloped by Atari users, then publishes a quar-
terly catalog that lists the programs available.
You can obtain many good programs through
theAPX.
In addition to Atari, other sources of programs
are companies that make software for many
kinds of computers. No single independent soft-
ware house, as they are called, has as many titles
exclusively for Atari computers as Atari itself. But
when you count up all of these companies and
the total programs they produce for Atari com-
puters, they comprise a large percent of the
commercial programs available for your system.
Users' groups and computer magazines are
sometimes good sources of inexpensive, excel-
lent programs. Because much of this software is
not copyrighted, it can easily be copied and/or
changed by anyone who uses it. This type of
software is called public domain software. You
will learn more about this type of software in the
next chapter.
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