Many people dread the blaring sound of an alarm clock, signaling the start of a busy workday. Others wish they weren’t already awake and that the sound had actually woken them up.Related video above: ...

Unlike traditional alarms that rely only on loud noise to abruptly pull you from your slumber, sunrise alarm clocks use gradual light exposure to cue your body to wake up. Over time (usually 20 to 40 ...