Job Control Language

Job Control Language (JCL) is a name for scripting languages used on IBM mainframe operating systems. It instructs the system on how to run a batch job or start a subsystem.
The purpose of JCL is to say which programs to run, using which files or devices for input or output. It can indicate under what conditions to skip a step.
There are two distinct IBM Job Control languages: 
They share some basic syntax rules and a few basic concepts, but are otherwise very different.