Posted March 8, 2008, 1:55 PM.

Daylight Saving Time shifts one hour of daylight from the morning to the evening.

This year in the United States, DST begins on March 9th at 2am, and ends on Sunday, November 2nd.

The Energy Policy Act of 2005 lengthened Daylight Saving Time by several weeks, beginning in 2007. Prior to that, DST began on the first Sunday in April and ended on the last Sunday in October.

DST is not observed in Arizona and Hawaii.