GNU
GNU i/ɡnuː/[1][2] is a Unix-like computer operating system developed by the GNU Project. It is composed wholly of free software as intended to be a "complete Unix-compatible software system"[3][4][5]GNU is a recursive acronym for "GNU's Not Unix!",[3][6] chosen because GNU's design is Unix-like, but differs from Unix by being free software and containing no Unix code.[7]
Development of GNU was initiated by Richard Stallman in 1983[3][8]and was the original focus of the Free Software Foundation (FSF), but no stable release of GNU yet exists as of October 2014.[3][9][10][11]However, non-GNU kernels, most famously the Linux kernel, can also be used with GNU software.[12][13][14] The combination of GNU software and the Linux kernel is known as Linux or GNU/Linux (seeGNU/Linux naming controversy).
Stallman views GNU as a "technical means to a social end."