Atari XL User Manual

CHAPTER 1
COMPUTERS AND PROGRAMS
Despite everything you may have heard about
computers being hyperintelligent machines which
are on the point of taking over the world, a
computer is not really intelligent at all. A
computer is at heart little more than a high-speed
adding machine, similar to an electronic calculator,
but with more sophisticated display and memory
facili ties.
The feature that gives computers their immense
flexibility and potential is this: they can store lists
of instructions which they can read through and
obey at very high speed. These lists of instructions
are called programs, and most of this book is
concerned with how these programs are written.
The computer instructions which form programs
must follow certain rules, or the computer will not
be able to understand them. The rules for wri ting
programs resemble the rules of a spoken language,
and so the set of instructions is often said to form a
programming language. There are many different
computer programming languages; the one that
the Atari XL understands (in common with most
other personal computers) is called BASIC. (The
name BASIC is an acronym for Beginners' AII-
purpose Symbolic Instruction Code.)
A
programming language is much simpler than a
human language because computers, for all their
power, are not as good at understanding languages
as people are. The BASIC language used by the
1

Atari XL Specifications

General

Brand	Atari
Model	XL
Category	Desktop
Language	English