GNU is a prominent free software project that aims to promote the development and distribution of free software. Founded by Richard Stallman in 1983, GNU provides a comprehensive collection of software tools and operating systems that are freely available for modification and redistribution. The project is best known for its role in the development of the GNU operating system, which is often used in conjunction with the Linux kernel to create fully functional operating systems. GNU emphasizes the principles of software freedom and advocates for users' rights to use, study, modify, and share software.