The TRIPOS operating system was developed in 1978 at the Computer Laboratory in Cambridge University. Most of Tripos was implemented in BCPL. The kernel and device drivers were implemented in Assembly language. Tripos was ported to a number of machines, including the Data General Nova 2, the Computer Automation LSI4, plus Motorola 68000 and Intel 8086 based hardware, and included support for the Cambridge Ring local area network. More recently, Martin Richards (Tripos' originator) produced a port of Tripos to run under Linux, using BCPL Intcode.

Tripos provided features such as pre-emptive multi-tasking (using a simple highest priority free-to-run scheduler), a hierarchical file system and multiple command line interpreters.

It formed the basis for much of the code of early versions of the AmigaOS.

Compare with the much older meaning of "tripos", as in "Natural Sciences Tripos".

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