UNIX in Dictionary

Unix (which stands for Uniplexed Information and Computing System according to AbbreviationFinder) is a portable, multi-tasking, multi – user operating system; developed in principle in 1969 by a group of employees of Bell Laboratories of AT & T, among which Ken Thompson, Dennis Ritchie and Douglas McIlroy.

“After thirty years of its creation, UNIX is still a phenomenon”

Until 2009, the owner of the UNIX® brand was The Open Group, an industry standardization consortium. From March of 2010 and after a long legal battle, this happened again become the property of Novell, Inc. Only fully compatible systems and are certified by the specification Single UNIX Specification can be called “UNIX®” (others they are called “Unix-like” or “Unix-like”). The term “traditional Unix” is sometimes used to refer to Unix or an operating system that has the features of UNIX Version 7 or UNIX System V.

The brand

This would be how UNIX looked around the late 1980s using the X Window System created by MIT.

UNIX is a registered trademark of The Open Group in the United States and other countries. This mark can only be applied to operating systems that comply with the ” Single Unix Specification ” of this organization and have paid the established royalties.

In practice, the term UNIX is used in its sense of family. It also applies to multi-user systems based on POSIX (such as GNU / Linux, Mac OSwhich, in its version 10.5 has already achieved UNIX certification, FreeBSD, NetBSD, OpenBSD), which do not seek UNIX certification because it is expensive to products intended for the final consumer or freely distributed on the Internet.

In these cases, the term is usually written as ” UN * X “, “* NIX”, or “* N? X”.


Unix Families Diagram.

As can be deduced from this brief historical overview, there are several families of the UNIX operating system, which have evolved independently over the years. Each family is distinguished not so much by its technical differences as by its differences in intellectual property. It is observed that all families have been contaminated, directly or indirectly, by other families.

Most significant UNIX families

  • AT&T: The family that originated from AT&T UNIX. Considered the “pure” and original UNIX family. Its most significant operating systems are UNIX System III and UNIX System V.
  • BSD: family originated by the licensing of UNIX to Berkely. BSD was rewritten to not incorporate AT&T original intellectual property in version 4. The first implementation of the TCP / IP protocols that gave rise to the Internet is the TCP / IP BSD stack.
  • AIX: This family arises from the licensing of UNIX System III to IBM.
  • Xenix: family derived from the acquisition of the original rights of AT&T first by Microsoft and of this sold them to SCO.
  • GNU: In 1983, Richard Stallman announced the GNU Project, an ambitious effort to create a Unix-like system that could be freely distributed. The software developed by this project – for example, GNU Emacs and GCC – have also been a fundamental part of other UNIX systems.
  • Linux: In 1991, when Linus Torvalds began proposing the Linux kernel and gathering collaborators, the GNU tools were the perfect choice. When both elements were combined, they formed the basis of the operating system (based on POSIX) that today is known as GNU / Linux. The distributions based on kernel, the software GNU and other aggregates among which may be mentioned by Slackware Linux, Red Hat Linux and Debian GNU / Linux They have become popular with both computer hobbyists and the business world. Note that Linux is of independent origin, so it is considered a ‘clone’ of UNIX and not a UNIX in the historical sense.

The interrelationships between these families are as follows, roughly in chronological order:

  • The BSD family arises from the licensing of the original UNIX from AT&T.
  • Xenix also emerged by licensing the original UNIX from AT&T, although it was not yet owned by SCO.
  • AIX arises from the licensing of UNIX System III, but also incorporates intellectual property from BSD.
  • The original AT&T family illegally incorporates BSD intellectual property into UNIX System III r3.
  • The AIX family once again incorporates intellectual property from the AT&T family, this time from UNIX System V.
  • Linux incorporates BSD intellectual property, thanks to the fact that it is also released under an open source license called Open-source BSD.
  • According to SCO Group, Linux incorporates intellectual property from AIX, thanks to the collaboration of IBM in version 2.4, more still not proven, there is a judicial process in this regard: SCO Disputes on Linux.