Finally: The "fall back" part of Daylight Saving Time has come again -- giving all of us an extra hour of sleep Sunday morning.
Daylight Saving Time ends at 2 a.m. Sunday, which means that almost all Americans need to turn their clocks back Saturday night or Sunday by one hour.
The exceptions are Arizona, Hawaii, Guam and some of the American territories.
Lore has it that Daylight Saving was conceptualized by Ben Franklin to help conserve candles -- and he did publish a letter in France suggesting it -- but giving him credit for Daylight Saving Time is stretching his legacy. Modern Daylight Saving Time was the brainchild of George Vernon Hudson, who suggested changing clocks twice per year, ahead in spring and back in fall.
As a permanent, national policy, Daylight Saving is a relatively recent phenomenon. The country turned to Daylight Savings in both World War I and World War II, but went off Daylight Savings after the wars were over.
In 1973 -- when energy conservation was a national obsession -- Daylight Saving became law.
So, does Daylight Saving really save energy? A 2008 report to Congress by the Department of Energy said that the nation saves 1.3 terawatt-hours each year. (Yes, that's a lot. One terawatt-hour is enough energy to power a city of 200,000 people for an entire year.)
But other results are mixed. The Christian Science Monitor has reported that in Indiana, daylight saving time actually caused a 1 percent jump in electric use, because energy saved from reduced lighting in the summer months was canceled out by an increase in the use of heating and air conditioning.
Still, it's a routine that is as familiar to most of the U.S. as having to buy way too much candy for Halloween. And while you are at it, check your smoke detectors.
Fire officials use the end of Daylight Saving as a good reminder to change batteries in the detectors -- and to upgrade to photoelectric smoke detectors if they haven't already.