GNU Free Documentation License

From Encyclopedia of Cybersecurity

GNU Free Documentation License

The GNU Free Documentation License (GNU FDL or simply GFDL) is a copyleft license designed for the free documentation of software and other creative works. It is a part of the GNU Project, initiated by the Free Software Foundation (FSF), and is similar to the GNU General Public License (GPL) used for software. The GFDL allows anyone to freely copy, modify, and distribute a work, as long as the modified version is also distributed under the same license terms.

Key Features

Some key features of the GNU Free Documentation License include:

  • Copyleft Requirement: The GFDL requires that any derivative work based on a GFDL-licensed document must also be licensed under the GFDL, ensuring that the freedoms granted by the license are preserved in all subsequent versions.
  • Verbatim Copies: The license allows for the distribution of verbatim copies of the work without modification, provided that the copyright notice and license terms are included with the copy.
  • Modification and Distribution: The license permits the modification and distribution of the work, including translations, adaptations, and compilations, as long as the resulting work is also licensed under the GFDL.
  • Commercial Use: The GFDL allows for the commercial distribution of works under the license, including for-profit publications and products, as long as the license terms are followed.

Use Cases

The GNU Free Documentation License is commonly used for:

  • Documentation: The GFDL is often used for the documentation of free and open-source software projects, allowing users and developers to freely access, modify, and distribute documentation alongside the software itself.
  • Educational Materials: The license is used for educational materials, textbooks, and manuals, allowing educators and students to freely access and modify educational resources.
  • Wikis: The GFDL was used by Wikipedia and other Wikimedia Foundation projects until 2009 when they migrated to the Creative Commons Attribution-ShareAlike (CC BY-SA) license.

Compatibility

The GNU Free Documentation License is not compatible with some other free licenses, such as the Creative Commons Attribution-ShareAlike (CC BY-SA) license, due to differences in their copyleft requirements. However, it is possible to dual-license works under the GFDL and another compatible license to accommodate different use cases and distribution channels.

Criticism

The GFDL has been criticized for its complexity and the difficulty of complying with its copyleft requirements, particularly for works that are distributed in multiple formats or media. Some projects have chosen to avoid the GFDL in favor of simpler and more widely accepted licenses, such as the Creative Commons licenses.

Conclusion

The GNU Free Documentation License is a copyleft license designed for the free documentation of software and other creative works. While it provides a legal framework for the distribution and modification of works, its complexity and compatibility issues have led some projects to choose alternative licensing options.