Aug 07

Beerware is software that is released under a very liberal license.  The Beerware license provides the end user with the right to use a software program and its source code for any purpose.  Should the user ever meet the program’s author, the user is encouraged to buy the author a beer.

The term was invented by John Bristor in 1987.  Many variations have been implemented, including the short and sweet Beerware license by Poul-Henning Kamp:

/*
 * ----------------------------------------------------------------------------
 * "THE BEER-WARE LICENSE" (Revision 42):
 * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
 * can do whatever you want with this stuff. If we meet some day, and you think
 * this stuff is worth it, you can buy me a beer in return Poul-Henning Kamp
 * ----------------------------------------------------------------------------
 */

Source: Wikipedia