| Developer | Burroughs / Unisys |
|---|---|
| Written in | ESPOL, NEWP |
| Working state | Current |
| Source model | Source available |
| Initial release | 1961 |
| Latest release | 20.0[1] / May 2021 |
| Platforms | Burroughs large systems including the Unisys Clearpath/MCP |
| Default user interface | Text user interface |
| License | Proprietary |
| Official website | Unisys ClearPath |
The MCP (Master Control Program) is the operating system of the Burroughs B5000/B5500/B5700 and the B6500 and successors, including the Unisys Clearpath/MCP systems.
MCP was originally written in 1961 in ESPOL (Executive Systems Problem Oriented Language). In the 1970s, MCP was converted to NEWP which was a better structured, more robust, and more secure form of ESPOL.
The MCP was a leader in many areas, including: the first operating system to manage multiple processors, the first commercial implementation of virtual memory, and the first OS written exclusively in a high-level language.