Timeline: 40 years of Unix

writes Linux, an open-source OS kernel inspired by Minix.

1992

The Linux kernel is combined with GNU to create the free GNU/Linux operating system, which many refer to as simply "Linux."

1993

AT&T sells its subsidiary Unix System Laboratories and all Unix rights to Novell. Later that year Novell transfers the Unix trademark to the X/Open group.

Microsoft introduces Windows NT, a powerful 32-bit multiprocessor operating system. Fear of NT will spur true Unix standardization efforts.

1994

NASA invents Beowulf computing based on inexpensive clusters of commodity PCs running Unix or Linux on a TCP/IP LAN.

1996

X/Open merges with Open Software Foundation to form The Open Group.

1999

U.S. President Clinton presents the National Medal of Technology to Ken Thompson and Dennis Ritchie for their work at Bell Labs.

2002

The Open Group announces Version 3 of the Single UNIX Specification (formerly Spec 1170).

Sources: Peter H. Salus, A Quarter Century of Unix ; Microsoft; AT&T; The Open Group, Wikipedia and other sources.

Next: On the shoulders of giants: Three Unix movers and shakers

Gary Anthes is a former Computerworld national correspondent.