This document summarizes key concepts around copyright including:
- Works in the public domain are not covered by intellectual property rights, have expired copyrights, or had copyrights forfeited. Mass digitization provides shared services to support research and teaching.
- Orphan works are copyrighted works whose owners cannot be contacted. Libraries display orphan works with notices that use is not guaranteed and can be used for any purpose to reduce risks.
- Express and implied licenses determine how copyrighted content found online can be used without permission. Posting infringing works can lead to legal consequences.
- Fair use allows limited use of copyrighted works without permission based on four factors analyzing the use, work, amount used,