VSAM stands for Virtual Storage Access Method and it was introduced by IBM in 1970’s. As name suggests, it is an access method intended to function in a virtual storage environment of MVS, z/OS. VSAM is high performance access method and acts as an interface between application program and physical operation of storage devices.

VSAM’s role is to provide an easiest way for program to store/retrieve data to/from an external device without concerning about physical details of transferring data bytes between program and I/O devices. VSAM can be used in COBOL or CICS in the mainframe for data manipulation on files

It can be helpful for any readers who has basic knowledge of software programming concepts and very basic knowledge of Job Control Language (JCL) and COBOL programming. Having understanding of any file handling concepts will be plus point and will make it easier for you to better understand VSAM concepts

This tutorial can be helpful for any software programmer who wants to learn and understand VSAM. Also, it will useful for mainframe professionals who wants to revise mainframe VSAM concepts.