Correction appended Nov. 2, 8:42 am ET
Daylight Saving Time is one of the universe’s great mysteries, like the afterlife, or who really killed JFK. It was one of the things you assumed you’d never understand. But it’s time for TIME to break down Daylight Saving Time.
First of all, it ends this weekend (Saturday night going into Sunday, to be exact), having started way back in March. And since we spring forward and fall back, we’ll all be getting one extra hour of sleep Sunday morning. Hooray!
Daylight Saving Time dates back to the good ole’ days when we did everything based on when we had sunlight. It got more serious when Benjamin Franklin decided to be “that guy,” suggesting we all get up earlier to save money on candles. Thanks, Benji. It was a major blow to all the unhappy, unhealthy, and unwise people who love to snooze.
The practice wasn’t formally implemented until World War I, when countries at war started setting their clocks back to save on coal. Daylight Saving was repealed during peacetime, and then revived again during World War II. More than 70 countries currently practice Daylight Saving Time, because they think it saves money on electricity (in the U.S., Arizona and Hawaii have opted out).
But studies show that Daylight Saving Time actually results in a one percent overall increase in residential electricity. And that it messes with sleeping patterns. Oh, and also it may cause heart attacks, according to the American Journal of Cardiology. So it’s no surprise that more and more countries are reevaluating whether to hold on to this relic from the past.
But like all great mysteries, the answers only beget more questions: Does your iPhone automatically update for Daylight Saving Time?
Actually, yes, it does.
Correction: This article was originally updated without revising the date Daylight Savings Time ends.