Get ready to change your clocks.

Daylight saving time begins Sunday, March 12 at 2 a.m. The change to DST pushes the clock up one hour to move more daylight into the evening. And while cell phones and technology has made the process easier, plenty of people still set their clocks ahead one hour before going to bed Saturday night.

Daylight saving time begins on the second Sunday in March each year and ends on the first Sunday in November. In 2023, the second Sunday of November falls on Nov. 5.

The switch to DST was first made during World War I to conserve fuel for the war effort. The law was repealed after the war ended but was reestablished by Congress during World War II due to energy consumption. The time change became law in 1966 when President Lyndon Johnson signed the Uniform Time Act, establishing the start and end times within standard time zones. The policy, regulated by the Department of Transportation, aims to save energy, reduce traffic fatalities, and reduce crime.

DST isn’t observed in all states. Arizona and Hawaii do not participate in changing the clocks and efforts are underway in at least 18 other states – including Alabama – to do away with the practice. Doing away with it entirely would take Congressional efforts, according to the National Conference of State Legislatures.