MVS for OS/390 Primer - Mainframe Series Author:David Shelby Kirk Conceptional view of the largest and best-known proprietary operating system. Operating system and how the components parts are structured. TSO, IMS, CICS, and DB2 and how they relate to MVS (OS/390). Job, task, and data management. Environment control, history, on-line access and databases. Skill requirements with skill matrix.