# Creative Commons (CC)
Creative Commons is a nonprofit organization founded in 2001 by Lawrence Lessig, Hal Abelson, and Eric Eldred. It provides a set of standardized copyright licenses that allow creators to grant specific usage permissions to the public while retaining some rights — a middle ground between full copyright ("all rights reserved") and public domain ("no rights reserved").
CC licenses are composable from four elements: Attribution (BY), ShareAlike (SA), NonCommercial (NC), and NoDerivatives (ND). These combine into six standard licenses plus the CC0 public domain dedication.
## License Types
| License | Allows | Requires |
|---------|--------|----------|
| **CC BY** | Any use including commercial | Attribution |
| **CC BY-SA** | Any use including commercial | Attribution + same license on derivatives |
| **CC BY-NC** | Non-commercial use | Attribution |
| **CC BY-NC-SA** | Non-commercial use | Attribution + same license on derivatives |
| **CC BY-ND** | Sharing only (no derivatives) | Attribution |
| **CC BY-NC-ND** | Non-commercial sharing only | Attribution |
| **CC0** | Anything (public domain) | Nothing |
## Openness Spectrum
| Most Open | | | Most Restrictive |
|-----------|--|--|------------------|
| CC0 | CC BY | CC BY-SA | CC BY-NC-ND |
CC BY-SA is the "copyleft" license — similar in spirit to the GPL in [[Open Source]] software. [[Wikipedia]] uses CC BY-SA for all its content.
## Impact
Creative Commons licenses are used on over 2 billion works worldwide. They underpin major knowledge-sharing platforms ([[Wikipedia]], Khan Academy, Flickr, MIT OpenCourseWare) and have become the default licensing framework for open educational resources, open access research, and open data.
## References
- https://creativecommons.org
- https://en.wikipedia.org/wiki/Creative_Commons
## Related
- [[Open Source]]
- [[Wikipedia]]
- [[Collective Intelligence]]