Copyright-free works refers to works which are not, or no longer, are protected by copyright.
These are generally works of which the copyright holder has died 70 years or more ago, works that the copyright holder has made free of rights, or works that are free of rights as specified by law.
Use-free works are works which are protected under copyright, but which the copyright holder has made ‘free to use’.
These works often come with a requirement regarding their use. One of the most common requirements is the requirement to reference the original source.
The Creative Commons are license requirements under which use-free works are provided.
To summarize:
Use-free works are protected under copyright but can be used freely as long as the requirements regarding their use are met.
Copyright free works are not protected by copyright.
