B[1]

Ken Thompson, 1970

A systems language written for Unix on the PDP-11. Derived from BCPL, and very similar to it except for syntax. B was the predecessor of C. It was used as the systems language on Honeywell's GCOS-3 operating system.

"The Programming Language B", S. C. Johnson & Brian W. Kernighan, CS TR 8, Bell Labs (Jan 1973).