Two Tools to Better Understand Copyright and Using Someone's Material

I heard to a couple of tools from the American Library Association that might prove useful - either in checking whether a use is permitted yourself or sending to those who would use your work without permission. The digital slider lets you choose a time range and other conditions to indicate whether something is in the pubic domain or if you would have to seek permission. The fair use checklist offers no such certain an answer, but it lists many of the considerations in a favoring/opposing fair use structure.