UNIX

UNIX
Type:	Time-sharing
Creator:	Ken Thompson, Dennis Ritchie and Douglas McIlroy at Bell Labs
Multitasking:	Multi-tasking with swapping/paging (latter added in a later version)
Architecture:	Originally PDP-7, then PDP-11; now cross-platform.
Date Released:	1969

Unix (officially trademarked as UNIX® - the documentation switched from using 'UNIX' to 'Unix' as of V7) is a computer operating system originally developed in the 1970s by a group of AT&T employees at Bell Labs including Ken Thompson, Dennis Ritchie and Douglas McIlroy.

Today's Unix systems are split into various branches, developed over time by AT&T as well as various commercial vendors and non-profit organizations. A number of clones of Unix, which share the interfaces, and 'look and feel', but no code, have also been produced; most notably, Linux.

Notable versions

Versions of relevance for hobbyists include (note that 'Version' in early UNIXes refers to the revision of the 'UNIX Programmer's Manual'; UNIX didn't really have coordinated distros before about V6):

• Unix "version 0" for PDP-7
• UNIX V1 - The first version of UNIX that has been recently made to run on the PDP-11
• UNIX V3 - The first version with pipes
• UNIX V4 - The first version with the kernel written in C
• UNIX V5 - The first version with complete source and binaries available
• UNIX V6 - The first widely distributed version; the last before branches started to appear
• Unix V7 - One of the most complete, and the last generally available and PDP-11 version of Research UNIX
• Unix/32V - A port of Seventh Edition to the VAX-11/780

Unix then went commercial and was sold, in a number of releases. (Below is an early ad for AT&T UNIX.)

• Unix SYSIII
• Unix SYSV
• Unix SYSVr2
• Unix SYSVr3
• Unix SYSVr4

Unix ad

CSRG releases

Meanwhile the Computer Systems Research Group‎ kept on releasing newer BSD UNIX's, mostly for the VAX, derived from 32V. These had wide distribution, and tremendous impact; they were a major step in UNIX's road to its current ubiguity.

Descended from there are several popular versions:

• FreeBSD focuses on providing a system geared towards a single user.
• NetBSD will run on a variety of 32-bit older systems from the VAX to the Amiga.
• OpenBSD derived from the NetBSD project will run on all kinds of systems.

See also

• Unix OS's
• Unix-based OS's
• UNIX file system
• BSD Fast File System

External links

• The Unix Heritage Society
  • The Unix Tree - Complete source for many early versions of Unix
• The Unix Heritage Wiki
• An Oral History of Unix - Lengthy interviews with Thompson, Ritchie, McIlroy, etc

Fun links

• The Unix Power Classic: A book about the Unix Way and its power - Hacker-oriented version of the Dao De Jing
• Rootless Root: The Unix Koans of Master Foo