"Free software" is the term coined in 1983 by Richard Stallman (known as RMS) to describe software which can be run, studied, modified, and redistributed. To advertise his views and promote free software, including the GNU project, Stallman founded the Free Software Foundation (FSF) in 1985. The FSF publishes the most frequently cited definition of "free software" but others exist, including the Debian Free Software Guidelines. In addition, informal definitions exist within the BSD-based operating system communities, the main divergence being that they disagree with the use of copyleft.
In 1998 Bruce Perens and Eric S Raymond launched a program to market free software "because it works, not because it's the only right thing to do," under the alternative label "open-source software." To this end they founded the Open Source Initiative (OSI). This term is currently in widespread use but is also an occasional source of friction. Other names in use include "free and open-source software" (FOSS); "free/libre/open-source software" (FLOSS); and "libre software" or "software libre", from the French word libre meaning free but lacking the "without cost" ambiguity.
Free software exists in an environment which includes laws, standards, and technology. These things can encourage, allow, or inhibit free software. Current issues, sometimes perceived as threats to free software or related more general freedoms, include the following: