GNU Manifesto
The GNU Manifesto was written by Richard Stallman to gain support and participation in the GNU Project. In the GNU Manifesto, Stallman listed four freedoms essential to software development: freedom to run a program for any purpose, freedom to study the mechanics of the program and modify it, freedom to redistribute copies, and freedom to improve and change modified versions for public use. To implement these freedoms, users needed full access to code. To ensure code remained free and provide it to the public, Stallman created the General Public License (GPL), which allowed software and the future generations of code derived from it to remain free for public use. Some complications arose, however, when certain software was grandfathered in the law of GPL because of code it derived from.
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