Many people seem to believe that as long as you don’t make money off of a project that uses materials under copyright, you are not breaking the law
People can use Your work as part of their (i.e. wallpapers, non profit games etc) as long as copyrighted item is only part of their project (ofc Your permision will be advisable) BUT righteufull owner can shut a project, wallpaper or w/e he wants (if it uses copyrighted item ) to as its his right.
Some examples of what i’m talkin about:
You make a home video when Your kids play around, theres a radio on and some song is audible. Then You share this movie with Your friends or family and voila You break the law – You illegally distributed song (or part of it).
You making the webpage and create banner using Your favorite game character covered by Your own logo. (webpage is about same game that character on banner is from) You have used copyrights protected item – You break the law