This guide identifies sources of free images from libraries, museums, archives, and historical societies. Scholarly, non-profit organizations such as the National Audubon Society may also be referenced.. Commercial image sources are not included.
Attribution and citation are similar, but not identical. A quick definition:
Attribution is giving credit to the creator of an image or other material in whatever manner that creator has specified. It's their stuff, and you're using it for free, so it's only fair to give credit as requested. The website or webpage where you obtained the material will almost always tell you the wording they'd like you to use.
Citation is an integral part of scholarship, in which you name all the sources used in your research as a matter of intellectual honesty. This applies to text (books, articles, encyclopedia entries) and non-text material like images, sound files, statistical tables, and so on. There are several standardized formats for citations, and your professor will tell you which one they want you to use. Online guides to common citation styles.
More on attribution vs. citation from open.michigan.
"The public domain" means works that are no longer protected by copyright, or where the creator of the work has explicitly waived their right to copyright protection.
Copyright is not an issue for class assignments and term papers, IF your professor is the only person who will see what you turn in. You could photocopy an image of a comic book character to illustrate your analysis of the symbolism of their crime-fighting costume, for example. (You would still have to cite where you obtained the image.)
BUT if your paper or content is put on a public website (as many class projects are) you must observe copyright restrictions. Works in the public domain are safe to use because they are no longer protected by copyright, or never were.
A Creative Commons license is a mechanism by which the creator of a resource (text, image, video, etc.) can make it available to others.
The creator can choose whether the license allows the work to be modified or only used in the exact form it is downloaded, and whether the work can be used by anyone or only for noncommercial purposes.
Learn all about Creative Commons licenses at creativecommons.org.
Ruth Ann Jones
Stephen O. Murray and Keelung Hong Special Collections
Michigan State University Libraries
American Antiquarian Society (Worcester, MA, USA) Digital Image Archive
British Library (London, UK) Image Albums on Flickr.
Calisphere (California, USA) Includes collections from all 10 University of California campuses
Digital Public Library of America (no bricks-and-mortar museum; headquartered in Boston, MA, USA)
Getty Museum (Los Angeles, CA, USA) Search Gateway, Open Content Images
Library Company of Philadelphia (Philadelphia, PA, USA) Digital Collections
Library of Congress Digital Collections (Washington DC, USA)
Los Angeles County Museum of Art (Los Angeles, CA, USA)
Metropolitan Museum of Art (New York, NY, USA) Open Access Artworks
Morgan Library & Museum (New York, NY, USA) Collections Online
National Archives and Records Administration (Washington, DC, USA) advanced catalog search
National Archives and Records Administration (Washington, DC, USA) public domain images on Flickr
National Audubon Society (New York, NY, USA) images from Birds of America
National Gallery of Art (Washington, DC, USA) NGA Images
New York Public Library (New York, NY, USA) Public Domain Digital Collections
Rijksmuseum (Amsterdam, The Netherlands) The RijksStudio
Smithsonian Institution Libraries (Washington, DC, USA) image galleries.