COBOL - How to use CICS

What is CICS and how to use it.

A CICS application is a collection of related programs that together perform a business operation, such as processing a travel request or preparing a company payroll. CICS applications execute under CICS control, using CICS services and interfaces to access programs and files.

CICS® stands for "Customer Information Control System." It is a general-purpose transaction processing subsystem for the z/OS® operating system. CICS provides services for running an application online, by request, at the same time as many other users are submitting requests to run the same applications, using the same files and programs.