General Resources - Links to sites which may have a mixture of public domain, creative commons licensing, or other restrictions.
Public Domain Images - All images on this page are considered to be in the public domain, either because their copyright expired (and was not renewed) or because the author specifically released his/her images to the public domain. Anything published before 1923 is also considered public domain.
Creative Commons - Guide to the types of creative commons licensing and links to sites which will allow you to specifically search for images with these licenses.
Governmental Sites - Most of the information on these governmental sites is considered to be public information/public domain, but there may be specific restrictions to use. These sites may also ask or require that you credit the source.
Images at Penn - Browse collections from the University of Pennsylvania. Images found in these databases may be subject to restrictions but may generally be used for educational purposes by Penn students, faculty, and staff.
Even if images are in the public domain, there may be a few restrictions to their use. Here are some common restrictions to keep in mind:
Public domain images have no restrictions to use, as in you may alter, change, redistribute, adapt, etc. the image for private or commercial use. A work published before 1923. Below are a few examples of other ways an image may become part of the public domain.
Sometimes, a person dedicates his/her work to the public domain:
Other times, the image may have originally had copyright, but once that copyright expired (i.e., it was never renewed, a certain number of years have passed after the author died, etc.), the image became part of the public domain:
*NOTE: NO ATTRIBUTION REQUIRED FOR WORKS IN THE PUBLIC DOMAIN*
Images in the public domain may also be used to create derivative works. One common example is Marcel Duchamp's L.H.O.O.Q., which is a derivative work of Leonardo Da Vinci's Mona Lisa:
Works under a Creative Commons license, as well as many of the governmental sites, may require that you attribute the author/source/organization.
Architect of the Capitol
Creative Commons License from Flickr:
*Check with the individual author/organization for preferences on attribution*