It is safe to say that time is a universal concept. While humans might be the only beings to track time as such, the whole universe is influenced by it. But how did we first start tracking time?
Did we use the sun, the moon, or the stars? What role does Earth's rotation play in how we track time? And what about clocks?
It's about time we answer these and many other questions. Click through the following gallery and lose yourself in this insightful chronology of time.