Copy-free: A type of licensing that makes the distribution of software available at no charge for noncommercial uses.
Trademark: A name, symbol, or other device used to identify a product, officially registered and legally restricted to the use of the owner or manufacturer.
Creative Commons: Organization that collects copy-free works, and distributes it ; One of several copyright licenses that allow the distribution of copyrighted works. The licenses differ by several combinations that condition the terms of distribution.
Royalty free: The right to use copyrighted material or property without needing to pay license charges for each use, per volume sold, or some time period of use, or sales. [Usually related to music]
GNU license: A free-software license that promotes the distribution of free works. [Similar to Creative Commons but for software]
Public Domain: Works that have no restrictions, and available or belonging to the public.
If something is copyrighted, it is likely to be reliable.
If something is copy free, question the reliability.

