CP/CMS

CP/CMS (Control Program/Cambridge Monitor System) was a time-sharing operating system of the late 60s and early 70s, known for its excellent performance and advanced features. It had three distinct versions:

• CP-40/CMS, an important "one-off" research system that established the CP/CMS virtual machine architecture
• CP-67/CMS, a reimplementation of CP-40/CMS for the IBM System/360-67, and the primary focus of this article
• CP-370/CMS, a reimplementation of CP-67/CMS for the System/370 – never released as such, but became the foundation of IBM's VM/370 operating system, announced in 1972.