copyleft

Etymology
Pun on, which refers to using copyright laws for purposes that are in some ways contrary to copyright's original intent.

Noun

 * 1) The philosophy of using copyrights to enforce freedom of information, especially software source code.
 * They believe in copyleft because they want their software to be used freely by anyone.
 * 1) A software license that follows this philosophy.
 * I have placed my program under copyleft.
 * The GNU General Public License is a copyleft licence.

Translations

 * French: gauche d'auteur,
 * German:
 * Russian: копилефт, авторское ле́во
 * Vietnamese: bản quyền ngược

Verb

 * 1)  To license under a copyleft license.
 * Linus Torvalds copylefted the Linux kernel.

Etymology
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