Oh sure, there are flip-up digital clocks and all manner of mechanical seven-segment displays, but this one seems to be quite unique, and very pleasing.

You see this most often on digital clocks. Complete this interactive activity to understand the 12 and 24-hour clock. Then put your knowledge to the test. There are lots of different types of clocks.

On the front of a building in New York City, above a branch of the ubiquitous Starbucks coffee chain, there is a clock. It is no ordinary clock, the 200 Water Street clock is an art installation ...