# A Brief History Of Time Keeping

How do we measure time? Why do we measure time? What is the basis for measuring time? Who set the rules? Why is a second as long as it is? Who/what keeps this exact measurement of the second? Answers ahead!

A day is almost exactly twenty-four hours long. A year is exactly three hundred sixty five days and a quarter day long. Four quarter days add up every four years to give one additional day: 29th Feb in a leap year. This system is the basis for each unit of time we measure. A day has to be twenty four hours, an hour sixty minutes, and a minute sixty seconds.

This is convention but there is a logic behind it. We could have had a hundred minutes in an hour or 45 seconds in a minute, but the Babylonians had their own number system going on. Brain Stuff:-

### Now that the why is done with, let’s move to how.

The very first clocks that humans used were called sundials, where the sun’s position in the sky was used to tell time.
Here’s how a simple sundial works.

#### Now Coming To A Quartz Clock

The Engineer Guy explains it all.

#### The Atomic Clock

The atomic clock is just an augmented quartz clock. When the quartz gets old and its frequency starts to die, the atom (i.e. Caesium) is used to give it a nudge and bring it back to life. Here’s how:-

### Conclusion

I know I should instead make a video blog, but whatever. Time is nothing more than a set of assumptions we’ve created for ourselves to ease our lives. Why does time always flow forwards? Why does time change with change in gravity? These are some questions we have no answer to, but this collection of videos was meant to snap you out of the illusion of time that we live in and view it as a quantum.