Starting in 2007, daylight time began in the United States on the second Sunday of March and ended last week on the first Sunday in November. On the second Sunday in March, clocks were set ahead one hour at 2:00 a.m. local standard time, which bacame 3:00 a.m. local daylight time. On the first Sunday this November, clocks were set back one hour at 2:00 a.m. local daylight time, which became 1:00 a.m. local standard time. These dates were established by the Energy Policy Act of 2005.
Not all places in the U.S. observe daylight time. In particular, Hawaii and most of Arizona do not use it. Indiana adopted its use beginning in 2006.
In 2007, daylight time ended on November 4. In 2008, daylight time begins on March 9 and ends on November 2.
Many other countries observe some form of “summer time,” but they do not necessarily change their clocks on the same dates as the U.S.
That said, be sure you punctuate properly:
— eastern standard time (no caps); EST
— central daylight time; CDT
— mountain standard time; MST
— Pacific daylight time; PDT
— Greenwich mean time; GMT
— daylight saving time (not savings)