The GNU project was launched in September 1983 by Richard M. Stallman to create a complete operating system of Free Software. Software development work started the following January. Stallman established the Free Software Foundation in October 1985 to assist administrative, legal, and organisational aspects of the GNU project and also to spread the use and knowledge of Free Software. The main licences of the GNU project are the GNU General Public License (GPL) and the GNU Lesser General Public License (LGPL, originally called GNU Library General Public License).
Over the years they have become established as the most widely used licences for Free Software. The GNU project consists of numerous smaller sub-projects maintained by volunteers or businesses or combinations of the two. These sub-projects themselves are also called “GNU projects” or “GNU packages. ” The name of the GNU project is derived from the recursive acronym “GNU’s Not Unix. ” Unix was a very popular operating system in the 80s, so Stallman designed GNU to be mostly compatible with Unix so that it would be convenient for people to migrate to GNU.
The name acknowledges that GNU learned from Unix’s technical design, but also importantly notes that they are unrelated. Unlike Unix, GNU is Free Software. Being Unix-like, GNU is modular in design. This means that third party components can be inserted into GNU. Today, it is very common for people to use a third party kernel called Linux with GNU systems. Many people use the name “Linux” for this variant of GNU, but this prevents people from hearing of the GNU project and its goal of software freedom.
FSFE asks people to use the term “GNU/Linux” or “GNU+Linux” when refering to such systems. Stallman founded the Free Software Foundation in 1985 to support the movement. The philosophy of the movement is to give freedom to computer users by replacing proprietary software under restrictive licensing terms with free software, with the ultimate goal of liberating everyone “in cyberspace” – that is, every computer user. Members of the free software movement believe that all users of software should have the freedoms listed in the free software definition.
Many hold that it is immoral to prohibit or prevent people from exercising these freedoms and that these freedoms are required to create a decent society where software users can help each other, and to have control over their computers.  Some adherents to the free software movement do not believe that proprietary software is strictly immoral.  They argue freedom is valuable (both socially and pragmatically) as a property of software in its own right, separate from technical quality in a narrow sense.
The Free Software Foundation also believes all software needs free documentation (in particular because conscientious programmers should be able to update manuals to reflect modification that they made to the software), but deems the freedom to modify less important for other types of written works.  Within the free software movement, the Floss manuals foundation specializes on the goal of providing such documentation. Members of the free software movement advocate that works which serve a practical purpose should also be free.