Below we have listed good sources of background information, including a list of websites on related topics.
Geology and Geologic Time: This page presents a brief history of the Geologic Time Scale with links to a discussion about plate tectonics.
Geologic Time Machine: Explore the stratigraphy, ancient life, localities, and tectonics of different time periods, eras, and eons on the web.
Fossils, Rocks, and Time: This site covers topics of how the time scale was created, the relative time scale, fossil succession, and the absolute time scale.