Atari 400 User Manual page 8

One of the main differences in the types of com-
puters is how much each can do. A computer
contains a certain number of memory chips,
which allow it to store information. For com-
puters, memory is measured in units called bytes.
Each byte holds one character (letter, number, or
symbol) of information. One kilobyte, or K as it
is commonly called, is equal to approximately
1,000 bytes of memory. For example, if your com-
puter comes with 16K of memory, this means
that it can store appr.oximately 16,000 characters
of information at one time.
Different types of Atari computers come with
different amounts of memory. The larger the
amount of memory, the more the computer can
do. In fact some of the more complex programs
you can buy for your computer require a certain
amount of memory in order to work properly.
You can buy additional units of memory for your
computer if you need more, which you will learn
about later in this guide. Let's take a look at the
Atari models 400, 800, and 1200XL.
Atari 400
The Atari 400 was introduced in late 1979. The
first units made contained 8K or 16K of memory,
while the latest models made contain 16K. The
400 features a flat, touch-sensitive membrane
keyboard, rather than one more like an electric
typewriter. (A membrane keyboard is one that
has a flat surface instead of raised keys.) While
the 400's membrane keyboard is not great for
toUCh-typing or entering long program listings,
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