IBM 1620 - Page 45

Block Diagramming
Block diagramming is a technique of schematically showing the steps which the
computer must take to produce th~ answers required by the problem.
Diagrams serve two purposes:
1. They offer an easy notation for analyzing the steps required in the solution
of a problem.
2. They provide the basic documentation in the form of a "map" of the
program, so
that someone unfamiliar with the program can easily de-
termine
what the program does and how it does it.
It is for these reasons that diagramming is not only highly recommended,
but is often required at data processing installations.
Techniques of diagramming vary greatly, as do
the symbols used. In addi-
tion,
diagramming may be very general, or extremely detailed to the point where
every machine instruction is included.
The more complete the diagram, the easier the job of actually writing the
program; however, initial analysis of a problem can usually be noted only in
major steps.
Only simple diagramming techniques will be explained here.
44.1