GNU

GNU , or in some countries/'nju:/) is a computer operating system composed entirely of free software. Its name is a recursive acronym for GNU's Not Unix; it was chosen because its design is Unix-like, but differs from Unix by being free software and containing no Unix code. Development of GNU was initiated by Richard Stallman and was the original focus of the Free Software Foundation (FSF).

GNU is developed by the GNU Project, and programs released under the auspices of the project are called GNU packages or GNU programs. The system's basic components include the GNU Compiler Collection (GCC), the GNU Binary Utilities (binutils), the bash shell, the GNU C library (glibc), and GNU Core Utilities (coreutils).

GNU is in active development. Although nearly all components have been completed long ago and have been in production use for a decade or more, its official kernel, GNU Hurd, is incomplete and not all GNU components work with it. Thus, the third-party Linux kernel is most commonly used instead. While this kernel has not been officially adopted by the GNU project, some third-party software is included, such as the X.Org release of the X Window System and the TeX typesetting system. Many GNU programs have also been ported to numerous other operating systems such as Microsoft Windows, BSD variants, Solaris and Mac OS.

The GNU General Public License (GPL), the GNU Lesser General Public License (LGPL), and the GNU Free Documentation License (GFDL) were written for GNU, but are also used by many unrelated projects.