A sure sign of spring: it’s time this weekend for the biannual tinkering with clocks. Daylight Saving Time officially begins at 2 a.m. Sunday, March 9, when clocks should be set ahead to 3 a.m. DST ends at 2 a.m. on Nov. 2, when the lost hour of sleep is returned.

Sunrise on Sunday will occur at 7:50 a.m. School children and folks who work 8-5 days will find the sky a bit dimmer than usual on Monday morning, but they’ll be rewarded with a longer evening. Sunset will occur at 7:31 p.m.

Daylight Saving Time has a long history in the United States and the world.

The idea was first proposed by Benjamin Franklin in 1784, as a way to save candles by rising earlier and taking advantage of natural light. An entomologist in New Zealand, George Vernon Hudson, made a proposal in 1895. There was some interest, but no action.

Its “invention” is generally credited to William Willett, an Englishman who came up with the idea of moving clocks forward 20 minutes on each of four Sundays in April and back on four Sundays in September, according to timeanddate.com. A bill was introduced in the House of Commons in 1905, but never enacted.

Daylight Saving Time was first used by Germany and Austria in 1916 to conserve fuel used to produce electricity for the war effort. Several European nations followed suit, and in 1918, the United States adopted a law that both set standard time zones and summertime daylight saving time. After the war, it was so unpopular (mostly because people rose earlier and went to bed earlier than they do now, according to webexhibits.org) that the law was repealed.

Daylight saving time continued as a local option in some states and large cities.

President Franklin D. Roosevelt initiated year-round DST (war time) from Feb. 2, 1942 to Sept. 30, 1945.

There was no federal legislation regulating daylight saving time from 1945 to 1966, creating chaos for the transportation and broadcasting industries.

A Committee for Time Uniformity discovered that on one 35-mile stretch of Route 2 from Moundsville, W. Va., to Steubenville, Ohio, travelers passed through seven time changes. The Uniform Time Act of 1966 attempted to end the inconsistencies.

In 1974, after the Organization of Petroleum-Exporting Countries (OPEC) imposed an embargo against the United States, President Richard Nixon signed the Emergency Daylight Saving Time Energy Conservation Act. A 55-mile-per-hour speed limit was also enacted.

Legislation was tweaked in 1986 and again in 2007, when the time was extended from the second Sunday in March to the first Sunday in November.

Scientific American reported in 2009 that the U.S. Department of Transportation trimmed the national electrical usage by roughly 1 percent, compared with standard time.

The magazine also reported on a 2006 study in Indiana, which found a 1 percent increase in residential electricity use, due to increased demand for cooling on summer evenings and heating on late spring and early fall mornings.

The U.S. Department of Energy concluded that the four-week extension of time in 2007 saved 1.3 trillion watt-hours, enough to power 100,000 households for a year.

Hawaii and Arizona (with the exception of the Navajo Nation) do not observe daylight saving time. The federal law does not require any state to spring forward and fall back, but if they choose to observe DST, must follow the starting and ending times set by law.