There are also three buttons which control the brightness and allow the time to be set. Be sure to check out the video below of this one-of-a-kind clock in action.

According to National Today, the punch clock is celebrated on "Punch The Clock Day" every year on Jan. 27. Other names for the punch clock include time clock, time recorder and clock card machine ...

What if you build a clock that displayed the time not just on its own, but in its shadows as well? [Lewis] from [DIY Machines] has done just that, with a nifty 3D-printed shadow clock build. The cl… ...

For example, to get the most accurate results from the NIST-F1 cesium clock, the current U. S. civilian time standard, clock performance must be averaged over 400,000 sec (or about five days).