Twice a year, Americans reset their clocks and lose an hour of sleep. The tradition may feel like a modern nuisance, but it began as a wartime policy during World War I. At 2 a.m. local time Sunday, ...

(CNN) — At the dawn of the nuclear age, scientists created the Doomsday Clock as a symbolic representation of how close humanity is to destroying the world. On Tuesday, nearly eight decades later, the ...