An illustrated history of timekeeping from ancient times to the present. Includes information on ancient calendars, early clocks, a revolution in timekeeping, world time scales and time zones, and the NIST standards.

Scroll down this page to see the various topics addressed on this website. Learn a "brief history of the Western Calendar" as well as information about the ancient calendars of the world, including the Sumerian, Egyptian, and Greek...

The concept of a year in time and the various kinds of year used in human timekeeping are discussed.