Encyclopedias

Britannica Concise

Brief entries on general-interest subjects adapted from the full-length Encyclopedia Britannica.

Encarta

Advertisement-supported encyclopedia developed by Microsoft. Many brief articles can be read for free, but most in-depth entries require a paid subscription.

Columbia Encyclopedia

One of the many full-text works offered for free (but advertising-supported) viewing by Bartleby. Entries here are full-length, taken directly from the current edition of the respected Columbia Encyclopedia.

Wikipedia

Perhaps the most popular site on the World Wide Web, the Wikipedia offers free access to lengthy articles on a wide variety of general and specialized subjects. Articles here are written and edited by the general public and are frequently modified. Be warned that at any given time a Wikipedia article may contain misguided, irrelevant, or false information.

Symbols: An Online Encyclopedia of Western Signs and Ideograms

A unique encyclopedia detailing the history and usage of many common and unusual symbolic markings.