The History of Timekeeping

Telling time has always been important to people. Long ago, people used the sun and stars to know what time it was. They invented sundials, water clocks, and hourglasses. Today, clocks and watches tell us the exact time down to the second.

Early Ways to Tell Time

Ancient Egyptians used sundials that told time by the shadow of the sun. Water clocks measured time by letting water drip slowly from a container. Hourglasses used sand flowing through a narrow opening. These tools helped people plan their days and know when to plant crops.

Mechanical and Digital Clocks

The first mechanical clocks were built in Europe in the 1300s. They had gears and weights but no minute hands at first. Pendulum clocks were invented in the 1600s and were much more accurate. Today, atomic clocks are so precise they lose less than one second in millions of years.

Fun Facts

• The oldest known sundial is from ancient Egypt and is about 3,500 years old.
• Before clocks, some towns hired people called knocker-uppers to wake others by tapping on windows.
• An atomic clock is so accurate it would only lose one second in about 300 million years.

Did You Know?

The minute hand was not added to clocks until the late 1600s because earlier clocks were not accurate enough to show minutes.