What is GNU?

GNU is a Unix-like operating system that is free software—it respects your freedom. You can install versions of GNU (more precisely, GNU/Linux systems) which are entirely free software. What we provide.

The GNU Project was launched in 1984 to develop the GNU system. The name “GNU” is a recursive acronym for “GNU's Not Unix!”. “GNU” is pronounced g'noo, as one syllable, like saying "grew" but replacing the r with n.

A Unix-like operating system is a software collection of applications, libraries, and developer tools, plus a program to allocate resources and talk to the hardware, known as a kernel.

The Hurd, GNU's own kernel, is some way from being ready for daily use. Thus, GNU is typically used today with a kernel called Linux. This combination is the GNU/Linux operating system. GNU/Linux is used by millions, though many call it “Linux” by mistake.

What is Free Software?

“Free software” is a matter of liberty, not price. To understand the concept, you should think of “free” as in “free speech”, not as in “free beer”.

Free software is a matter of the users' freedom to run, copy, distribute, study, change and improve the software. More precisely, it refers to four kinds of freedom, for the users of the software:

• The freedom to run the program, for any purpose (freedom 0).
• The freedom to study how the program works, and adapt it to your needs (freedom 1). Access to the source code is a precondition for this.
• The freedom to redistribute copies so you can help your neighbor (freedom 2).
• The freedom to improve the program, and release your improvements to the public, so that the whole community benefits (freedom 3). Access to the source code is a precondition for this.