IMS (Information Management System) is a database and transaction management system that was first introduced by IBM in 1968. Since then, IMS has gone through many changes in adapting to new programming tools and environments. IMS is one of two major legacydatabase and transaction management subsystems from IBM that run on mainframeMVS (now z/OS) systems. The other is CICS. It is claimed that, historically, application programs that use either (or both) IMS or CICS services have handled and continue to handle most of the world's banking, insurance, and order entry transactions.