AS400
Also known as: iSeries, IBM System i, IBM i, AS/400
IBM's Application System/400, a midrange business computing platform introduced in 1988, now evolved into IBM i on IBM Power Systems.
The AS400 (Application System/400) is an integrated midrange business computing system introduced by IBM on June 21, 1988. It was designed as a fully integrated platform combining hardware, operating system, relational database (DB2), and security into a single system. The platform is known for extraordinary reliability, application longevity, and a security model that remains among the most comprehensive in the industry. Over its history the name has changed from AS400 to iSeries (2000) to IBM System i (2006) to IBM i on Power (2008), but the underlying architecture and application compatibility have been preserved through each transition. Thousands of organizations worldwide continue to run business-critical applications on IBM i today, including ERP systems, manufacturing control, order management, and financial applications originally written for the AS400.