GNU is an operating system and an extensive collection of computer software. GNU is composed wholly of free software, most of which is licensed under the GNU Project's own GPL. 

"GNU" is a recursive acronym for ""GNU's Not Unix!"", chosen because GNU's design is Unix-like, but differs from Unix by being free software and containing no Unix code. The GNU project includes an operating system kernel, GNU HURD, which was the original focus of the Free Software Foundation (FSF). However, non-GNU kernels, most famously Linux, can also be used with GNU software; as the Hurd kernel is not yet production-ready, this is how the GNU system is usually used. The combination of GNU software and the Linux kernel is commonly known as Linux (or less frequently GNU/Linux; see GNU/Linux naming controversy). 

Richard Stallman, the founder of the project, views GNU as a "technical means to a social end". Relatedly Lawrence Lessig states in his introduction to the second edition of Stallman's book "Free Software, Free Society" that in it Stallman has written about "the social aspects of software and how Free Software can create community and social justice." 

Development of the GNU operating system was initiated by Richard Stallman while he worked at the Massachusetts Institute of Technology (MIT) Artificial Intelligence Laboratory. It was called the GNU Project, and was publicly announced on September 27, 1983, on the net.unix-wizards and net.usoft newsgroups by Richard Stallman. Software development began on January 5, 1984, when Stallman quit his job at the Lab so that they could not claim ownership or interfere with distributing GNU components as free software. Richard Stallman chose the name by using various plays on words, including the song "The Gnu".
What is GNU?
What does Linux have to do with it?
Who was the founder?
How did he view GNU?
Did he write any books?
What was it called?
Who developed GNU?
Where was he working at the time?
When was the project announced?
What happened on January 5?
Who quit their job?
operating system
GNU is an operating system
non-GNU kernels
However, non-GNU kernels, most famously Linux
Richard Stallman
Richard Stallman, the founder of the project,
"technical means to a social end"
Richard Stallman, the founder of the project, views GNU as a "technical means to a social end". 
Yes
Lawrence Lessig states in his introduction to the second edition of Stallman's book "Free Software, Free Society"
"Free Software, Free Society"
Stallman's book "Free Software, Free Society"
Richard Stallman
Development of the GNU operating system was initiated by Richard Stallman
MIT
Development of the GNU operating system was initiated by Richard Stallman while he worked at the Massachusetts Institute of Technology (MIT) Artificial Intelligence Laboratory
September 27, 1983
It was called the GNU Project, and was publicly announced on September 27, 1983
Software development began
Software development began on January 5, 1984
Stallman
when Stallman quit his job 