FlexOS was a modular real-time multi-user multi-tasking operating system (
RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. It was developed by
Digital Research's Flexible Automation Business Unit in
Monterey, California since 1986 and was marketed since January 1987 as a reengineered derivation of Digital Research's
Concurrent DOS 286 multiuser multitasking operating system.