Libre Licences
Libre licences are licences pertaining to copyright in which the copyright owner has granted the freedoms specified in the definitions of libre software, libre knowledge and libre cultural works. A libre resource (one so-licensed or in the public domain) is free of any restrictions which might prevent users from being able to exercise these freedoms (such as DRM or patent-encumbrance). For example, of the still active Creative Commons licences, Creative Commons Attribution, Attribution-ShareAlike and Zero are libre licences.
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