Creative Commons (CC) licenses

The Creative Commons (CC) licenses are public copyright licenses that enables the free distribution of an otherwise copyrighted work. The standardized terms of these licenses are established by the Creative Commons global nonprofit organization, which has a network of staff, board, and affiliates around the world.

The right to distribute the copyrighted work worldwide for non-commercial purposes, and without modification, is the baseline term granted by all CC licenses. Further conditions are imposed by each of the 4 licenses, as follows:




Attribution (BY)

Licensees may copy, distribute, display and perform the work and make derivative works and remixes based on it only if they give the author or licensor the credits (attribution) in the manner specified by these. If they want to use the work without giving credit to the author or for endorsement purposes, they must get permission from the author first.

Share-alike (SA)

Licensees may distribute derivative works only under a license identical ("not more restrictive") to the license that governs the original work. Without share-alike, derivative works might be sublicensed with compatible but more restrictive license clauses, e.g. CC BY to CC BY-NC.)

Non-commercial (NC)

Licensees may copy, distribute, display, and perform the work and make derivative works and remixes based on it only for non-commercial purposes.

No Derivative Works (ND)

Licensees may copy, distribute, display and perform only verbatim copies of the work, not derivative works and remixes based on it.

These conditions can be further mixed, with the following most used types of licenses:

  1. Freeing content globally without restrictions (CCO)
  2. Attribution alone (CC BY)
  3. Attribution + ShareAlike (CC BY-SA)
  4. Attribution + Noncommercial (CC BY-NC)
  5. Attribution + NoDerivatives (CC BY-ND)
  6. Attribution + Noncommercial + ShareAlike (CC BY-NC-SA)
  7. Attribution + Noncommercial + NoDerivatives (CC BY-NC-ND)


For software, Creative Commons includes also three free licenses created by other institutions:

  1. The BSD License and class of license (BSD-like), a family of permissive free software licenses, imposing minimal restrictions on the use and redistribution of covered software.
  2. The GNU Lesser General Public License (LGPL), which was written for the GNU C Library to allow it to be linked with proprietary software, and include clauses to protect users against hardware restrictions that prevent user to run modified software on their own devices.
  3. The GNU General Public License (GPL), which guarantee users freedom to share and change free software, and being the most commonly used free software license. It gives all recipients of a program the right to run, copy, modify and distribute it, while forbidding them from imposing further restrictions on any copies they distribute, being also referred to as “copyleft”. Copyleft is a general method for making a program free software and requiring all modified and extended versions of the program to be free software as well.

A large number of other licenses are know, either for software or other purposes (e.g. documentation, fonts, testimony, designs, etc.), with a comprehensive list being maintained by the GNU Project:



  1. U.S. Copyright Office. Url:
  2. The EU copyright legislation. Url:
  3. Creative Commons. Url:
  4. Creative Commons Licenses. Wikipedia. Url:
  5. Licenses, GNU Operating System. Url:
  6. R. Rabbit. Why Free Software is more important now than ever before. Wired, 2013. Url:
  7. D.A. Wheeler, 2015. Why Open Source Software/ Free Software (OSS/FS, FLOSS, or FOSS)? Look at the numbers! Url: