Jens Olsen's World Clock is a big clock with a lot of parts that shows the time in different cities around the world. Imagine you have a toy clock with numbers 1 to 12 on it. When the big hand of the clock points to number 12, it means it's exactly 12:00 noon. Similarly, when the big hand points to number 3, it means it's 3:00 in the afternoon.
Now, Jens Olsen's World Clock works similarly, but it shows the time in different cities not just one. The clock has many parts that move together to show different times in different cities. There are 12 small clocks inside the clock but each showing a different city. These cities include Copenhagen (where the clock is located), New York, Tokyo, and Sydney.
The clock uses gears and mechanical parts to keep track of time in each of these cities. It also takes into consideration things like daylight saving time and leap years to ensure that the time shown is always accurate.
Overall, Jens Olsen's World Clock is a very complicated and impressive machine that tells us the time in different places around the world!