Beerware is a tongue-in-cheek software license with permissive terms, which grants the right to do anything with the source code, assuming the license notice is preserved.
[3] Should the user of the code consider the software useful, they are encouraged to buy the author a beer "in return" if they ever meet.
The Humanitarian-FOSS project at Trinity College recognized the "version 42" beerware license variant as an extremely permissive "copyright only" and GPL-compatible license.
[2] Poul-Henning Kamp states preference of his Beerware license to other licenses, such as BSD and GPL, the latter of which he has described as a "joke".
[4] The full text of Kamp's license is:[5]