Free licenses are used to grant rights to all people in a world where all marketable content is protected by intellectual property laws by default. This includes everything from media (literary works, music, images, craftworks), software and hardware designs. Granting rights to the public is not easy because without strongly written licenses, the author of the content can be held liable for any damage caused by anyone using her works.

I have listed some free licenses which can be used to give legal rights to the public to freely use the works.

Media

Public Domain

CC0 1.0 Universal

Permissive

Creative Commons Attribution

Conditionally Permissive

Creative Commons Attribution NonCommercial

Copyleft

Creative Commons Attribution ShareAlike
Creative Commons Attribution NonCommercial ShareAlike

Non Commercial

Creative Commons Attribution NonCommercial
Creative Commons Attribution NonCommercial ShareAlike
Creative Commons Attribution NonCommercial NoDerivatives

Non Modifiable

Creative Commons Attribution NoDerivatives
Creative Commons Attribution NonCommercial NoDerivatives

Software

Legally Strong

Public Domain

Zero Clause BSD License

Permissive

MIT License
ISC License
BSD 3 Clause License

Copyleft

GNU AGPLv3
GNU GPLv3

Ethical

Hippocratic License

Legally Weaker

Public Domain

WTFPL
The Unlicense

Hardware

CERN OHL
Solderpad License

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