IMS is IBM’s premier transaction and pre-relational database management system, virtually unsurpassed in database and transaction processing availability and speed. IMS clients have trusted IMS with their most critical business asset—their operational data—for decades. Today’s IMS has only a superficial resemblance to the product that first shipped in 1969. However, an application program that ran on IMS in 1969 will still run today, unchanged, on the current release of IMS. From the beginning, IBM’s focus on the future of IMS has been unwavering. IMS continues to be a strategic component of today’s enterprise computing environments. This chapter highlights some of the history of IMS and describes how IMS.
