In the U.S., daylight savings started on Sunday March 13 at 2:00 a.m. and ended on Sunday November 6 at 2:00 a.m. In California, Daylight Saving Time was first observed in 1918, it is used to save energy and to make better use of our time in the daylight.  How this works is during the months in summer, we change our clocks by setting them to one hour ahead so that our evening daylight lasts an hour longer. When summertime comes to an end we must set our clocks an hour behind so now our sunsets are an hour earlier.