Pick operating system

The Pick operating system (often called just "the Pick system" or simply "Pick") is a demand-paged, multiuser, virtual memory, time-sharing operating system based around a unique "multivalued" database. It is used primarily for business data processing. Although it started on a variety of minicomputers, the system and various implementations eventually spread to a large variety of microcomputers and mainframe computers, and is still in use today.
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