What is Daylight Saving Time?

Sometimes called “fast time” or “summer time,” Daylight Saving Time (DST) temporarily extends the length of daylight because we move our clocks forward an hour in the spring, creating longer days. In the United States, we change our clocks in March. Most of the United States begins Daylight Saving Time at 2:00 A.M. on the second Sunday in March and reverts to standard time on the first Sunday in November (when we set our clocks back one hour). In the United States, each time zone switches at a different time. Different countries have different change dates. Although DST was first proposed by Benjamin Franklin in 1784, it began in the United States during World War I, primarily to save fuel by reducing the need to use artificial lighting. Although some states and communities observed DST between the wars, it was not observed nationally again until World War II. Today, most Americans continue to participate in DST to save energy, although Arizona and Hawaii are the two states that are exceptions to the rule.


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