GPL

GPL is a widely used free software license that guarantees end-users the freedom to run, study, share, and modify the software. The GPL was created by Richard Stallman for the GNU Project, a free and open-source software initiative launched by Richard Stallman in 1983, with the goal of creating a Unix-like operating system. The GPL is considered a copyleft license, which means that any software that uses or modifies GPL-licensed code must also be licensed under the GPL, as seen in projects like Linux kernel developed by Linus Torvalds and Git created by Linus Torvalds and Junio C Hamano. This ensures that the software remains free software and that the source code is always available, as required by the Free Software Foundation founded by Richard Stallman.

History and development

The GPL was first released in 1989 by Richard Stallman and the Free Software Foundation, with the goal of creating a license that would protect the freedom of end-users to use, modify, and distribute software. The GPL was influenced by the Berkeley Software Distribution (BSD) license, which was used by the University of California, Berkeley for their Unix operating system. The GPL has undergone several revisions, with the most recent version being the GNU General Public License, version 3 (GPLv3), which was released in 2007 and has been adopted by projects like Samba developed by Andrew Tridgell and Jeremy Allison. The development of the GPL was also influenced by the work of Lawrence Lessig and the Creative Commons organization, which aims to promote the use of open content licenses like the Creative Commons Attribution-ShareAlike license used by Wikipedia.

Terms and conditions

The GPL requires that any software that uses or modifies GPL-licensed code must also be licensed under the GPL, as stated in the GNU General Public License, version 2 (GPLv2) and GNU General Public License, version 3 (GPLv3). This means that any derivative works of GPL-licensed software must also be licensed under the GPL, as seen in projects like Debian developed by Ian Murdock and Red Hat Enterprise Linux created by Red Hat. The GPL also requires that the source code of the software be made available to end-users, as required by the Free Software Foundation and the Open Source Initiative founded by Eric S. Raymond and Bruce Perens. This ensures that end-users have the freedom to modify and distribute the software, as guaranteed by the GNU Project and the Linux Foundation established by Jim Zemlin.

Versions and variants

There have been several versions of the GPL, including the GNU General Public License, version 1 (GPLv1), GNU General Public License, version 2 (GPLv2), and GNU General Public License, version 3 (GPLv3). Each version has introduced new terms and conditions, such as the requirement that patent holders license their patents under the GPL, as stated in the GNU General Public License, version 3 (GPLv3) and supported by the Software Freedom Law Center founded by Eben Moglen. There are also several variants of the GPL, including the GNU Lesser General Public License (LGPL) and the GNU Affero General Public License (AGPL), which are used by projects like MySQL developed by Monty Widenius and MariaDB created by Monty Program Ab. The LGPL is used for libraries and allows for the use of LGPL-licensed code in proprietary software, as seen in projects like Qt developed by Trolltech and KDE created by Matthias Ettrich.

Compatibility with other licenses

The GPL is compatible with several other free software licenses, including the MIT License used by X Window System developed by MIT Computer Science and Artificial Intelligence Laboratory and the Apache License used by Apache HTTP Server created by Apache Software Foundation. However, the GPL is not compatible with all free software licenses, such as the BSD License used by BSD operating systems developed by University of California, Berkeley and the Mozilla Public License (MPL) used by Mozilla Firefox created by Mozilla Corporation. This means that software that uses or modifies GPL-licensed code cannot be licensed under a non-compatible license, as stated by the Free Software Foundation and the Open Source Initiative. The GPL is also compatible with the Creative Commons licenses, such as the Creative Commons Attribution-ShareAlike license used by Wikipedia and the Creative Commons Zero (CC0) license used by Wikidata.

Impact and adoption

The GPL has had a significant impact on the development of free and open-source software, with many popular projects using the GPL, including the Linux kernel developed by Linus Torvalds and Git created by Linus Torvalds and Junio C Hamano. The GPL has also been adopted by many companies, including Red Hat and Novell, which use the GPL for their Linux distributions, such as Red Hat Enterprise Linux and SUSE Linux Enterprise. The GPL has also been used by many non-profit organizations, including the Free Software Foundation and the Linux Foundation, which aim to promote the use of free and open-source software. The GPL has also been recognized by the United Nations and the European Union as a key component of the free and open-source software movement, as seen in the European Union's Free and Open-Source Software (FOSS) policy and the United Nations World Intellectual Property Organization (WIPO) Copyright Treaty. The GPL has also been supported by many notable individuals, including Richard Stallman, Linus Torvalds, and Eric S. Raymond, who have contributed to the development of free and open-source software and the promotion of the GPL. Category:Software licenses