1.5 What are FSF, GNU, RMS, and GPL?

FSF

Free Software Foundation

GNU

GNU’s Not Unix

RMS

Richard Matthew Stallman

GPL

GNU General Public License

See the GNU web site for more information about the GPL.

The word “free” in the title of the Free Software Foundation refers to “freedom,” not “zero cost.” Anyone can charge any price for GPL-covered software that they want to. However, in practice, the freedom enforced by the GPL leads to low prices, because you can always get the software for less money from someone else, since everyone has the right to resell or give away GPL-covered software.