What is Copyleft

Is a general method for making a program or other work free, and requiring all modified and extended versions of the program to be free as well.

A general method for marking a creative work as freely available to be modified, and requiring all modified and extended versions of the creative work to be free as well.

The Free Software Fundation and some other associations, created this concept to label a set of licenses that defend different kinds of freedom in cultural creations. Those licenses are the legal base that allows the construction of a common repository of knowledge free to reach and adapt by everybody interested in. Wikipedia (2007) says: “Copyleft is a form of licensing and may be used to modify copyrights for works such as computer software, documents, music, and art. In general, copyright law allows an author to prohibit others from reproducing, adapting, or distributing copies of the author’s work. In contrast, an author may, through a copyleft licensing scheme, give every person who receives a copy of a work permission to reproduce, adapt or distribute the work as long as any resulting copies or adaptations are also bound by the same copyleft licensing scheme.”

A type of intellectual property license which uses copyright law to remove restrictions on the distribution of copies and modified versions of a work for others and which also requires the same freedoms be preserved in modified versions.

It is the practice of granting the right to freely distribute and modify intellectual property with the requirement that the same rights be preserved in derivative works created from that property.

Copyleft is a general method for making a program or other work free, and requiring all modified and extended versions of the program to be free as well. Copyleft says that anyone who redistributes the software, with or without changes, must pass along the freedom to further copy and change it. Copyleft guarantees that every user has freedom.

The practice of using copyright law in order to remove restrictions on the distribution of copies and modified versions of a work for others and require the same freedoms be preserved in modified versions.

The copyleft principle prevents the privatization of the whole or parts of the software that has a license that implements this principle.

Permission for everyone to run, copy, and modify the program, and to distribute modified versions, but no permission to add restrictions of one’s own.