The tags "anonymous artist" and "unknown artist" are mutually exclusive. Anonymous artists are artists who distribute their work anonymously under no online alias, whereas an unknown artist is tagged to a piece of art where the author's identity is simply not known.

This project isn't for those wanting to breeze through, some research legwork will have to be done in order to determine whether the artist wanted to be kept anonymous or whether no information can be gleaned. When in doubt, use "Unknown artist".