The highest category of taxonomic classification is the kingdom. This website from Palomar College presents the five kingdoms in an easy-to-read chart and discusses the Animalia and Plantae kingdoms in depth. After reading through the...

Describes the characteristics of the five kingdoms of living things - Monera, Protista, Fungi, Plantae, and Animalia.

Detailed information about each of the five kingdoms. Each kingdom is separately described, but information is also summarized in a table.

This site is a description of the history behind the 5 Kingdom system suggested by Robert Whittaker. An extensive list of resources is included.