ISeries

The IBM System i is IBM's previous generation of midrange computer systems for IBM i users, and was subsequently replaced by the IBM Power Systems in April 2008.

The platform was first introduced as the AS/400 (Application System/400) on June 21, 1988 and later renamed to the eServer iSeries in 2000. As part of IBM's Systems branding initiative in 2006, it was again renamed to System i. The codename of the AS/400 project was "Silver Lake", named for the lake in downtown Rochester, Minnesota, where development of the system took place.

In April 2008, IBM announced its integration with the System p platform. The unified product line is called IBM Power Systems and features support for the IBM i (previously known as i5/OS or OS/400), AIX and GNU/Linux operating systems.

The predecessor to AS/400, IBM System/38, was first made available in August 1979 and was marketed as a minicomputer for general business and departmental use. It was sold alongside other product lines, each with a different architecture (System/3, System/32, System/34, System/36).

Realizing the importance of compatibility with the thousands of programs written in legacy code, IBM launched the AS/400 midrange computer line in 1988. AS stands for "Application System." Great effort was made during development of the AS/400 to enable programs written for the System/34 and System/36 to be moved to the AS/400.

In 2000, in accordance with IBM's eServer initiative, the AS/400 series was rebranded as the eServer iSeries. In 2006, it was again rebranded as the IBM System i. In 2008, almost 20 years after being introduced, the System i and IBM System p product lines were combined into a new product line called the IBM Power Systems line.

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