The GNU project
The GNU Project 
i/ɡnuː/ is a free-software, mass-collaboration project, first announced on September 27, 1983 by Richard Stallman at MIT. Its aim is to give computer users freedom and control in their use of their computers and computing devices, by collaboratively developing and providing software that is based on the following freedom rights: users are free to run the software, share it (copy, distribute), study it and modify it. GNU software guarantees these freedom-rights legally (via its license), and is therefore free software; the use of the word "free" always being taken to refer to freedom.
In order to ensure that the entire software of a computer grants its users all freedom rights (use, share, study, modify), even the most fundamental and important part, the operating system (including all its numerous utility programs), needed to be free software. According to its manifesto, the founding goal of the project was to build a free operating system and, if possible, "everything useful that normally comes with a Unix system so that one could get along without any software that is not free." Stallman decided to call this operating system GNU (a recursive acronym meaning "GNU's not Unix"), basing its design on that of Unix, a proprietary operating system. Development was initiated in January 1984. In 1991, the kernel Linux appeared, developed outside of the GNU project by Linus Torvalds, and in December 1992 it was made available under version 2 of the GNU General Public License. Combined with the operating system utilities already developed by the GNU project, it allowed for the first operating system that was free software, known as Linux or GNU/Linux.
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