A Walk Through Time
An illustrated history of timekeeping from ancient times to the present.
Daylight Saving Time
Why do we use daylight savings time and who invented it?
Discover Magazine: Time Machine
Article explores a clock designed to keep accurate time for 10,000 years.
Latitude and Longitude
Introduction to latitude and longitude, a way of calculating exactly where you are anyplace on earth and a way to tell time.
Making a Horizontal Sundial
Learn how to make a sundial. Instructions are for beginners, intermediate, or advanced, and work for either the northern or southern hemispheres.
Making a Sun Clock
Before there were clocks, people used shadows to tell time. Learn how to make your own sun clock!
Science Museum - Atomic Clocks
Talks about how different types of atomic clocks work, and the history of their invention.
The Galileo Project - Pendulum Clock
Describes Galileo's work on pendulums and the pendulum clock.
The University of Houston College of engineering, describes how an hourglass works and also provides interesting facts about this timekeeper.
Just how do we measure time and what has Greenwich England got to do with it?
US Library of Congress - How does an hourglass measure time?
Answers questions about how an hourglass keeps time and what are the contributing factors determining how long an hourglass lasts.
What Time Is It!
Gives the current time, synchronized by NIST. Close to 100 different time zones supported, as well as the ability to select the default time zone.
When Does Daylight Savings Time Occur
Explanation of when and why we have daylight savings time.