MS/8

MS/8 or The RL Monitor System is a discontinued computer operating system developed for the Digital Equipment Corporation PDP-8 in 1966 by Richard F. Lary.

History

RL Monitor System, as it was initially called, was developed on a 4K PDP-8 with "a Teletype that had a paper tape reader and punch and.. a single DECtape." It was a disk oriented system, faster than its predecessor, the PDP-8 4K Disk Monitor System, with tricks to make it run quickly on DECtape based systems.
Still named RL, it was submitted to DECUS in 1970.
MS/8 was replaced by P?S/8 and COS-310.