Art Research and Finding Images: Images

• Know More Now: Searching Smarter in Google provides insight on utilizing Google's incredible searching power to your best academic advantage, featuring tips and tricks to search smarter, whether for text content or images.
• Public Domain Images provides an explanation of what it means when an image is available under public domain, outlines differences between public domain and creative commons images, discusses ethical responsibilities of users of images, and gives examples of types of images that are normally available under public domain.
• Find Creative Commons images with Image Search explains how to search for creative commons images in Google through the advanced image search page.

Archival and Digital Library Collections

• Digital Public Library of America searches millions of photographs, manuscripts, books, sounds, moving images, and more from libraries, archives, and museums around the United States.
• Library of Congress Digital Collections provides free and open access through the Internet to written and spoken words, sound recordings, still and moving images, prints, maps, and sheet music that document the American experience.
• British Library Flickr Stream contains over a million images from copyright-free books from the 17th, 18th and 19th Century.
• British Library Online Gallery contains 30,000 online searchable items made available. Create an account and curate your own images through the personal galleries feature.
• New York Public Library Digital Collections contains over 700,000 items from NYPL.
• Smithsonian Institution Digital Collections contains over 8.1 million cataloged items relating to Art, Design, History, Culture, Science, and Technology, with 860,477 images, videos, audio files, podcasts, blog posts and electronic journals available.

Art

• Los Angeles County Museum of Art (LACMA) allows searching collections by object, date, or subject. Tip limit your search to "show public domain images only."
• Getty Research Institute's Museum Collection provides free access to a growing number of digitized items from the Research Library, Special Collections, Photo Archive, and Institutional Archives. These materials range from the 15th century to the present and include books, photographs, manuscripts, archives, and works on paper.
• Harvard Art Museums - The Bauhaus is one of the first and largest collections relating to the Bauhaus, the 20th century’s most influential school of art and design. Active during the years of Germany’s Weimar Republic (1919–33), the Bauhaus aimed to unite artists, architects, and craftsmen in the utopian project of designing a new world.
• Metropolitan Museum of Art contains a broad range of digital images and data that document the rich history of the Museum, its collection, exhibitions, events, people, and activities.
• LIFE photo archive hosted by Google contains millions of (mostly unpublished) photographs from the LIFE photo archive, going back to the 1750s.

General

• The Public Domain Review is a not-for-profit project dedicated to showcasing the most interesting and unusual out-of-copyright works available online. It includes articles from leading scholars, writers, archivists, and artists, as well as curated collections of films, audio, images and texts.Tip: To search for images on this site, add site:publicdomainreview.org to your own keywords in a Google search.
• Public Domain Pictures provides some free stock photos posted by members of the site. Other stock photos are available for a small fee. You can also upload your own images for others to use. A toolbar at the top of the page provides many categories in which you can find images.
• Public Domain Archive contains hundreds of high resolution public domain images with new images added weekly. Some of these images are over 10MB in size, so if they take a little longer to load, that’s why.
• Flickr: Creative Commons provides images uploaded by Flickr account holders who have chosen to offer their work under Creative Commons license. There are different types of licenses under the Creative Commons license, and images are sorted by type of license.
• StockSnap includes hundreds of high resolution images added weekly. Free from copyright restrictions.
• Wikimedia Commons is affiliated with Wikipedia, specifically featuring images. Quality of photography is not guaranteed, but images are generally available at a high resolution.
• Openverse Search provides searchable content you can "share, use and remix," including content you can use for commercial purposes or modify, adapt, or build upon for your own purposes.
• U.S. Government Photos and Images (USA.gov) holds government photos and images sorted by topic, some are in the public domain or are U.S. Government works others may be copyrighted.
• WorldImages Kiosk is a searchable image database created by various faculty, staff and students of the CSU system. Global in coverage, it contains over 50,000 historical images from a wide variety of fields. These images are licensed under a Creative Commons license and may be used for non-profit, educational purposes as long as credit is given to the copyright holders who retain rights to the images.
• Pexels provides photos licensed under the Creative Commons Zero (CC0) license so the pictures are free to be used for any legal purpose.
• WP Tavern is a warm and inviting community where those interested in the software can hang out with fellow WordPressers to engage in enlightening discussions. This post is titled "13 Sources For Free Public Domain and CC0-Licensed Images."

Maps

• David Rumsey Historical Map Collection contains rare and mostly 18th and 19th century digitized items pertaining largely to North and South America.
• Perry-Castañeda Library Map Collection includes historical maps from all over the world.
• UCLA Digital Collections searches creative commons licence collections containing historical, global and local maps.

Science and Medicine

• Science History Institute Image Archive contains images and other materials related to the history of chemistry.
• Public Health Image Library contains public domain and copyright protected images, easily browsed by category.
• NASA Images contains image galleries pertaining to topics in astronomy, astrophysics, space, and related earth science subjects, as well as historical images.
• NASA Visible Earth is a collection of mostly public domain images of Earth taken from space.
• U.S. Geological Survey Photographic Collection is a collection of public domain images. Freely search and browse photographs taken during geologic studies from 1868 to the present.
• U.S. Dept. of Agriculture, Agricultural Research Service Image Gallery contains many copyright-free and public domain images. Browse the Agricultural Research Service images and find high-quality photos, easily by category.
• Government Resources for Images, hosted by the Library of Congress, is a list of image resources for the sciences.