Copyleft is a type of license agreement allowing the licensor or the user the legal liberty to use, modify, extend and redistribute a creative work and all its derivative works or forms (i.e. works based on or derived from it) against the popular mode of restrictive or condition licensing.


The copyright holder grants permission to the public including anyone who may want to utilize the work to copy and redistribute it in the same or in a modified form with the conditions that all such redistributions make the work available in a form that facilitates further modification and use the same license as granted from the original creator to the public