ArtLext - On-line Art Dictionary (http://artlex.com)
This on-line art dictionary encompasses over 2,400 entries arranged alphabetically.

iBiblio.org(http://www.ibiblio.org/collection/collection.php?primary=9)
Home to one of the largest "collections of collections" on the Internet, ibiblio.org is a conservancy of freely available information, including animation, architecture, art, cartoons, games, graphic arts, music, photography and film & performing arts. Ibiblio.org is a collaboration of the Center for the Public Domain and The University of North Carolina. 

Fine Arts Museum of San Francisco  (http://www.thinker.org)
This website contains images and information on more than 65,000 works produced by more than 15,000 artists, and images can be located by artist, title, country, time period, or keyword with the Imagebase, a search engine designed for this website. 

National Gallery of Art(http://www.nga.gov)
The renowned National Gallery, located in Washington D.C., provides excellent background essays and 16 virtual tours that include sculpture, European and American paintings, and prints dating from the Middle Ages to the present.  A search engine is also provided to search the nearly 100,000 works in the gallery. 

Web Museum, Paris (http://sunsite.unc.edu/wm)
The Web Museum offers informative essays regarding genres and styles, and also contains thousands of images.  A Famous Paintings database contains indexes of mostly American and European art by artists and themes from the 13th century to the present. 

World Art Treasures (http://sgwww.epfl.ch/BERGER)
This website, created by the Jacques-Edouard Berger Foundation, located in Lausanne, Switzerland, is a formidable virtual gallery of over 100,000 slides that include paintings, prints, sculpture, and other forms of art from Europe and Asia. 

World Wide Arts Resources (http://wwar.com)
Touted as the "largest gateway to arts in the world," this site, sponsored by the Metropolitan Museum of Art, includes links not only to paintings but also to art education, art history, as well as antiques and architecture. 

World Wide Web Sources for Art History (http://web.uflib.ufl.edu/afa/art/web-art.html)
The site links to sites related to art and art history. Sites are categorized into Metasites; Florida Sites; Specialized Sites; Museum and Gallery Sites; and Associations, Institutes, and Organizations. The variety of links available makes this site a good choice for research.