This chapter is only a background to your learning of JCL.
This
material will not be required later in the book, nor will you use
it directly in writing JCL. However, it is extremely important
that you understand the "surroundings" of a job in the computer so
that everything you will learn here will make sense and fall into
its right place.
First, what is JCL, Job Control Language?
It is a language that the programmer uses to communicate with the
Operating System of the computer to let it know what resources and
special conditions are needed to run programs.
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