Remember to set your clocks ahead one  hour tonight because Daylight Saving Time officially starts at 2 a.m.  on Sunday. It ends the first Sunday in November.
Benjamin Franklin first  thought up the idea of daylight saving in 1784. It wasn't instituted  until World War I, when it went into effect to save energy used for  lights.
 The Standard Time Act  established time zones and daylight saving in 1918, but it was  short-lived. Daylight saving was repealed the following year.
 
 The Uniform Time Act of  1966 established Daylight Saving Time throughout the United States and  gave states the option to exempt themselves. Hawaii and most of Arizona  do not follow Daylight Saving Time. Guam, Puerto Rico, the Virgin  Islands and American Samoa also skip out on the clock-changing fun.
Credit: 
http://www.cnn.com/2013/03/09/us/daylight-saving-time/