You may find images and other works that are protected by copyright. Literature, music, drama, pictures, graphics, sculptures, motion pictures, audiovisual works, sound recordings, architectural works, and other creative and intellectual works, published or unpublished are protected by copyright from the time of their creation. Essentially, this means the work belongs to its creator, and that any attempts to reuse or reproduce that work need to follow certain rules to abide by that copyright.
Any work created on or after January 1, 1978, is automatically protected from the moment of its creation. Copyright protection lasts for the duration of the author's life + 70 years. If the work is made for hire, it is protected for 95 years from publication or 120 years from creation, whichever is shorter (U.S. Copyright Office, 2012).
Public domain is a term that refers to creative materials where the copyright has expired or where no copyright is necessary. Creators can also place their work into the public domain on purpose. Like the name suggests, works in the public domain belong to the public - they are not owned by an individual creator. Works in the public domain can be used by anyone.
In general, copyrighted works enter the public domain 70 years after the death of the creator. If a work was created by a corporation, it enters the public domain 95 years from publication or 120 years from creation, whichever comes first.
All works published in the United States before 1928 are now in the public domain.
The Cornell University Libraries have published a chart to help identify when works fall in the public domain. You can view that chart here.
Fair Use is a doctrine that allows limited reproduction of works protected by copyright, without the need to request permission from the copyright owner. Uses that fall under "fair use" include commentary/criticism, parody, reporting, and research/scholarship. Many educational uses of protected works are considered fair use, but not all of them are. Copyright law provides four factors that must be weighed when determining whether fair use applies:
1. "The purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes"
This looks at whether you stand to make money from using the copyrighted work. If the copyrighted work is being used for financial gain (someone other than the copyright holder is making money off the copyrighted work), that is generally not considered fair use. If the copyrighted work is being used for educational purposes or for no monetary gain, it is more likely to be considered fair use.
2. "the nature of the copyrighted work"
Creative works (such as art, music, literature, etc.) tend to be less commonly viewed as fair use, because the nature of the work is entertainment or creative expression. Works where the nature of the work is informational, like scholarly papers, news items, or technical information, are more likely to be considered fair use because that promotes the spread of information.
3. "the amount and substantiality of the portion used in relation to the copyrighted work as a whole"
This looks at how much of the work is used. In general, the more of a copyrighted work you use, the less likely it is to be considered fair use. There is also a standard that considers the "heart" of a work, which is somewhat difficult to define but considers what the most important or memorable aspect of a work is. Reusing the "heart" of a work is less likely to be fair use.
4. "the effect of the use upon the potential market for or value of the copyright work."
Does your use of the copyrighted work make it less likely for the original copyright holder to make money or break into a new market? If so, it likely isn't fair use. One benefit of copyright is that it protects a creator's right to profit from their work. If your use interferes with that ability, it likely won't be fair use.
When attempting to determine if a particular use of a work is fair use you should asses the use according to each of the four factors. If all four indicate that it is likely fair use then it probably is. If one or more seem to indicate it is not fair use, then it likely is not.
The short answer is... Probably!
Education is generally considered fair use. Including a copyrighted photograph in a classroom presentation or research paper, with proper citation, probably does not interfere with the original creator's copyright. Think back to the first factor of fair use - use for nonprofit or educational purposes is generally considered fair use. You should make sure to properly cite any copyrighted material you are using.
However, if you plan to publish your paper or share your presentation publicly (outside of your class), you may need to seek permission from the copyright holder. This includes if you're posting your paper or presentation on a public web forum, like YouTube or social media. Because sharing your work publicly could result in financial gain (think about ad revenues on YouTube for example) or could affect the potential market for the copyrighted work, you may find it stops being fair use.
A Creative Commons license allows creators to grant public permission to use their work without needing express permission from the copyright holder. Creators can select which level of Creative Commons license to use and will disclose the licensing information along with the content. Once a creator applies a Creative Commons license to their work, that choice cannot be revoked and the license remains for the entire length of the material's copyright.
There are six types of Creative Commons licenses that provide a range of permission levels. View the list of licenses, including how to recognize them, on the Creative Commons website linked below.
Cornell University Libraries. (2023, August 14). Copyright term and the public domain. https://guides.library.cornell.edu/copyright/publicdomain
Creative Commons. (2019). About CC licenses. https://creativecommons.org/share-your-work/cclicenses/
Holy Cross Libraries. (2023, August 7). Copyright and fair use. https://libguides.holycross.edu/copyrightfairuse
MIT Libraries. (n.d.) Using copyrighted content. https://libraries.mit.edu/scholarly/copyright/using-copyrighted-content/
Stanford Libraries. (2023). Measuring fair use: The four factors. https://fairuse.stanford.edu/overview/fair-use/four-factors/
Stanford Libraries. (2023). Welcome to the public domain. https://fairuse.stanford.edu/overview/public-domain/welcome/
Stim, R. & Secor, G. (2023). Fair use: The 4 factors courts consider in a copyright infringement case. Nolo. https://www.nolo.com/legal-encyclopedia/fair-use-the-four-factors.html