FORT BELVOIR, Va. -- Daylight saving time returns this Sunday at 2 a.m. when most Americans set their clocks forward at 3 a.m.
Most people regard the change as a time when they lose one hour of sleep, but the practice extends evening daylight so days – particularly summer days – last longer.
Daylight saving time begins the second Sunday in March and ends the first Sunday in November, when clocks are adjusted one hour back to standard time.
The United States adopted daylight saving time when the Uniform Time Act of 1966 standardized time zones and daylight saving practices across the United States.
The act allowed states to pass laws exempting themselves. The only states that don’t observe daylight saving time are Hawaii and most of Arizona. It’s also not observed by these U.S. territories: American Somoa, Guam, Puerto Rico and the Virgin Islands.