Control Program Facility

The System/38 was a midrange computer server platform manufactured and sold by the IBM Corporation. The system offered a number of innovative features, and was the brainchild of Frank Soltis and Glenn Henry. Developed under the code-name "Pacific", the System/38 was made commercially available in August 1979.

The midrange predecessors to the System/38 included the System/3, System/32, and System/34. The System/38 offered more capacity than the previous System/34. The System/38 chronologically preceded the System/36, which was a successor to the System/34.

The System/38 was nearly called the System/380, and the AS/400 was nearly called the System/40.

The System/38 was superseded by the AS/400 (which also supported System/36 data & programs, at least to some extent). The AS/400 was primarily a re-marketing of the System/38, with some updates to the operating system. S/38 programs (with 'observability' intact) can still run on the AS/400 and successor systems.

The S/38's advanced operating system lives on with IBM's AS/400. Realising the importance of the thousands of lines of 'legacy code' (programs) written, 'AS' stands for 'Application System'. Great efforts were made by IBM to enable programs originally written for the System/34 and /36 to be moved to the AS/400. The AS/400 was replaced by the iSeries, which was subsequently replaced by the System i. In 2008, the System i was replaced by the IBM Power Systems. By contrast, competing proprietary computing architectures from the early 1980s such as Wang VS and Hewlett Packard's HP3000 have long been discontinued without a compatible upgrade path.

The AS/400 evolved into the iSeries, which in turn evolved into the System i (although the 'evolution' does include significant enhancements to hardware and operating system capabilities, the name change is usually considered more of an evolution in marketing). The System/38 legacy lives on in the enterprise-class IBM Power Systems series, which superseded System i in 2008, and which can run IBM i as well as AIX and Linux.

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