Encyclopedias contain factual articles on many subjects.

There are two types of encyclopedias -- general and subject. General encyclopedias provide overviews on a wide variety of topics. Subject encyclopedias contain entries focusing on one field of study.

• when looking for background information on a topic
• when trying to find key ideas, important dates or concepts

Examples

• Encyclopedia of Crime & Justice (subject encyclopedia)
• Encyclopedia Americana (general encyclopedia)