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Let's talk about time
Time is the continued progress of existence and events, in one direction, from the past through the present and into the future. We measure it to sequence events, to compare how long things take, and to coordinate across a planet of different clocks.
A short history of the hour
The Egyptians are often credited as the first to split the day into parts, using sundials to divide daylight into twelve. Around 147–127 BC the Greek astronomer Hipparchus proposed twelve hours of daylight and twelve of darkness based on the equinox — the 24 equal hours we still use today, though fixed-length hours only became common with mechanical clocks in the 14th century.
The calendar most of the world runs on, the Gregorian calendar, was introduced by Pope Gregory XIII in 1582 to correct an 11-minute-per-year drift in the older Julian calendar — keeping our dates aligned with the seasons across centuries.