Digitized images of art, architecture, and other forms of visual culture from around the world, from museums, archaeology, photo archives, slide collections, and art reference works.
Dates: BCE to present
Sources that are openly available for reuse are referred to as Public Domain, usually after copyright has expired or does not apply.
Copyright holders can choose to license their works with Creative Commons, which allows for various levels of use and remix restrictions. Visit the Yale University's Arts Library Digital Services guide to copyright page for more details on these topics. Georgetown has an excellent guide to the ins and outs of using images in publications.