Douglas McIlroy

b. 1932, Newton, Massachusetts · Head of Bell Labs CS research; inventor of Unix pipes

Also known as: McIlroy, Doug McIlroy

Douglas McIlroy headed the Bell Labs Computing Techniques Research Department, the group that produced Unix. His most influential technical contribution is the pipe (|), which joins one program's standard output to another's standard input — still the foundation of Linux shell composition.

He wrote several core utilities (echo, spell, diff, sort, join, graph, tr) and articulated the Unix philosophy ("write programs that do one thing and do it well") in the 1978 Bell System Technical Journal.