Alternative terms for free software

Alternative terms for free software, such as open source, FOSS, and FLOSS, have been a controversial issue among free and open source software users from the late 1990s onwards. These terms share almost identical licence criteria and development practices.

In the 1950s to the 1990s software culture, the "free software" concept combined the nowadays differentiated software classes of public domain software, Freeware, Shareware and FOSS and was created in academia and by hobbyists and hackers.

When the term "free software" was adopted by Richard Stallman in 1983, it was still ambiguously used to describe several kinds of software. In February 1986 Richard Stallman formally defined "free software" with the publication of the The Free Software Definition in the FSF's now-discontinued GNU's Bulletin as software which can be used, modified, and redistributed with little or no restriction, his four essential software freedoms. Richard Stallman's Free Software Definition, adopted by the Free Software Foundation (FSF), defines free software as a matter of liberty, not price and is inspired by the previous public domain software ecosystem. The canonical source for the document is in the philosophy section of the GNU Project website, where it is published in many languages.

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