Stallman pioneered the concept of copyleft, which uses the principles of copyright law to preserve the right to use, modify, and distribute free software.
He has been the GNU project's lead architect and organizer, and developed a number of pieces of widely used GNU software including, among others, the GNU Compiler Collection, GNU Debugger, and GNU Emacs text editor. With this, he also launched the free software movement. Stallman launched the GNU Project in September 1983 to write a Unix-like computer operating system composed entirely of free software. Stallman launched the GNU Project, founded the Free Software Foundation in October 1985, developed the GNU Compiler Collection and GNU Emacs, and wrote the GNU General Public License. Software that ensures these freedoms is termed free software. He campaigns for software to be distributed in such a manner that its users have the freedom to use, study, distribute, and modify that software. Richard Matthew Stallman ( / ˈ s t ɔː l m ən/ born March 16, 1953), also known by his initials, rms, is an American free software movement activist and programmer.
