Six things you need to know about daylight saving time

By Kori Rumore

Oct. 28, 2015 10 PM PT

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Daylight saving time, a change in the standard time designed to conserve energy and make better use of daylight, officially ends Sunday. This means at 2 a.m., clocks should "fall back" -- in other words, they should be set one hour behind. Daylight saving time officially begins again at 2 a.m. Sunday, March 13, and that's when clocks will "spring ahead" an hour.

The United States wasn't the first country to observe daylight saving time.
Associated Press
Benjamin Franklin is credited with first proposing the concept of daylight saving time in 1784. In an essay called "An Economical Project for Diminishing the Cost of Light," Franklin said the change would save, "a considerable number of candles." According to Time and Date, Germany was the first country to implement it during World War I on April 30, 1916.
Between Sept. 22 and Nov. 8, more than 60 countries will end daylight saving time but not on the same date.
Territories and states in these countries might also differ on the date when daylight saving time ends. More than 160 countries don't observe daylight saving time at all.
Countries that adjust their clocks to end daylight saving time
By date DST ends (includes only countries that began observing DST in March)
Sept. 22
Daylight saving time-observing countries
Others
Sept. 26
Daylight saving time-observing countries
Others
Oct. 23
Daylight saving time-observing countries
Others
Oct. 24
Daylight saving time-observing countries
Others
Oct. 25
Daylight saving time-observing countries
Others
Oct. 30
Daylight saving time-observing countries
Others
Nov. 1
Daylight saving time-observing countries
Others
Nov. 8
Daylight saving time-observing countries
Others
This topic has caused riots in Russia.
The country has changed its stance on daylight saving time several times since January 2011. President Vladimir Putin returned the country to standard time in October 2014.
It's federal law.
Library of Congress photo
» Daylight saving time, also known as "fast time" back in the day, had its first run in the U.S. when President Woodrow Wilson signed it into law in 1918 to support World War I efforts. It didn't last. The law was repealed seven months later.
» Robert Garland, a Pittsburgh industrialist, is considered the father of daylight saving time in the U.S. He learned of the concept in Britain.
» President Franklin D. Roosevelt launched year-round daylight saving time in the U.S. in 1942.
» It wasn't until the Uniform Time Act of 1966, however, that it was decided the U.S. would observe daylight saving time from the last Sunday of April to the last Sunday of October. (States could exempt themselves from this rule.)
» Congress extended the daylight saving time period to 10 months in 1974 and to eight months in 1975 to promote energy savings after the 1973 oil embargo.
» Further changes to the federal law were made in the 1970s and '80s.
» The Energy Policy Act of 2005, signed into law on Aug. 8, 2005, states daylight saving time begins the second Sunday in March and ends the first Sunday in November. Parts of Canada have also adopted the same change.
A few parts of the U.S. and its territories don't change time.
Arizona (except for the Navajo Nation), Hawaii, Puerto Rico, American Samoa and the U.S. Virgin Islands don't recognize daylight saving time.
U.S. Department of the Interior
Several others are trying to repeal daylight saving time.
Alaska: A state Senate bill that would not just eliminate daylight saving time but also add another time zone to the state didn't get a vote in the House this past session. Most of Alaska is in one time zone, although the far western end of the state is in the Hawaii-Aleutian time zone, which is one hour behind the rest of the state.
Idaho: State House Majority Leader Mike Moyle withdrew a bill he proposed that would have put Idaho on daylight saving time all year because such a move is against federal law. States have two daylight saving time options: stick with standard time year-round or change to daylight saving time in March. Yet, the federal government does allow some states to exempt themselves from time changes.
New Mexico: A bill that advanced to the state's Senate Judiciary Committee that would keep the state on daylight saving time year-round died this past session.