Encyclopedia

An encyclopedia, alternatively spelled as encyclopaedia or encyclopædia, is a type of reference work holding a summary of information from either a particular branch of knowledge, or all branches of knowledge. Encyclopedia entries are usually divided into articles or entries which can be usually accessed alphabetically by name. Encyclopedias have existed for over 2,000 years and modern encyclopedias have evolved from dictionaries around the 17th century. Examples of modern encyclopedias include Wikipedia, Wikania, and the Encyclopedia Britannica.