The Evolution of the UNIX(R) Time-Sharing System

This paper presents a brief history of the early development of the UNIX(R) operating system. It concentrates on the evolution of the file system, the process-control mechanism, and the idea of pipelined commands. Some attention is paid to social conditions during the development of the system. This paper is reprinted from Lecture Notes on Computer Science, No. 79, Language Design and Programming Methodology, Springer-Verlag, 1980.