The Free Software Definition written by

Richard Stallman Richard Matthew Stallman (; born March 16, 1953), also known by his initials, rms, is an American free software movement activist and programmer. He campaigns for software to be distributed in such a manner that its users have the freedom to u ...

and published by the

Free Software Foundation The Free Software Foundation (FSF) is a 501(c)(3) non-profit organization founded by Richard Stallman on October 4, 1985, to support the free software movement, with the organization's preference for software being distributed under copyleft ("s ...

(FSF), defines

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, ...

as being software that ensures that the end users have freedom in using, studying, sharing and modifying that software. The term "free" is used in the sense of "free speech," not of "free of charge." The earliest-known publication of the definition was in the February 1986 edition of the now-discontinued ''GNU's Bulletin'' publication by the FSF. The canonical source for the document is in the philosophy section of the

GNU Project The GNU Project () is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and Computer hardware, computing devi ...

website. , it is published in 39 languages. The FSF publishes a list of licences which meet this definition.

The Four Essential Freedoms of Free Software

The definition published by the FSF in February 1986 had two points: In 1996, when the gnu.org website was launched, "free software" was defined referring to "three levels of freedom" by adding an explicit mention of the freedom to study the software (which could be read in the two-point definition as being part of the freedom to change the program). Stallman later avoided the word "levels", saying that all of the freedoms are needed, so it is misleading to think in terms of levels. Finally, another freedom was added, to explicitly say that users should be able to run the program. The existing freedoms were already numbered one to three, but this freedom should come before the others, so it was added as "freedom zero". The modern definition defines free software by whether or not the recipient has the following four freedoms: Freedoms 1 and 3 require

source code In computing, source code, or simply code, is any collection of code, with or without comment (computer programming), comments, written using a human-readable programming language, usually as plain text. The source code of a Computer program, p ...

to be available because studying and modifying software without its source code is highly impractical.

Later definitions

In July 1997, Bruce Perens published the Debian Free Software Guidelines. A definition based on the DFSG was also used by the

Open Source Initiative The Open Source Initiative (OSI) is the steward of the Open Source Definition, the set of rules that define open source software. It is a California public-benefit nonprofit corporation, with 501(c)(3) tax-exempt status. The organization w ...

(OSI) under the name "''The Open Source Definition''".

Comparison with ''The Open Source Definition''

Despite the philosophical differences between the free software movement and the open-source-software movement, the official definitions of

by the FSF and of

open-source software Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Ope ...

by the OSI basically refer to the same software licences, with a few minor exceptions. While stressing these philosophical differences, the Free Software Foundation comments:

References

External links

The Free Software Definition
{{DEFAULTSORT:Free Software Definition, The Free software Free Software Foundation

The Four Essential Freedoms of Free Software

Later definitions

Comparison with ''The Open Source Definition''

See also

References

External links