A reference site allows you to search for information that has been collected in encyclopedias, almanacs, atlases, dictionaries, and other reference resources. Some reference sites, such as Encyclopedia Britannica Online, offer limited access to information from their encyclopedias at no charge and complete access for a fee. Other sites, such as Information Please and Bartleby.com, allow unrestricted access to recently published reference works, including the Columbia Encyclopedia, The Encyclopedia of World History, and The World Factbook.

One widely used reference site is Wikipedia, whose articles are collaboratively written by its readers. Because of its comprehensiveness, Wikipedia can serve as a useful starting point for research on a topic. However, because any reader can make changes to most of the pages on the site, it’s best to double-check any information you find there.

Leading reference search sites include the following: