Depending on the types of items (books, articles, films, sound recordings, archival materials, etc.), determining the copyright holder may be very straightforward, or it may be very complex. The resources below are intended to help you in determining who may hold the copyright to items you plan to use in your research and/or teaching.
According to their website, "Creative Commons is a nonprofit organization that enables the sharing and use of creativity and knowledge through free legal tools." The site provides free copyright licenses that enable copyright holders to "give the public permission to share and use [their] creative work — on conditions of [their] choice."
To read more about Creative Commons licenses and how they work, visit the links below.