The days are getting shorter and the nights are getting longer, signaling the approaching end of daylight saving time.

Like clockwork, the end of daylight saving time will occur in early November. However, the exact change date is different every year.

As the 2024 time change approaches in Illinois, here's what you should know about the “fallback.”

When do we change our clocks?

By federal law, Daylight Saving Time begins on the second Sunday in March and lasts through the first Sunday in November in most of the United States

This year that date falls on November 3rd, with clocks going back one hour at 2am.

What is Daylight Saving Time?

Daylight saving time is a time change that typically begins in spring and ends in fall, often referred to as “spring before” and “fall back.”

Under the terms of the Energy Policy Act of 2005, daylight saving time begins on the second Sunday in March and ends on the first Sunday in November.

On these days the clocks are either moved forward or back by one hour.

But that wasn't always the case.

The clocks previously went forward on the first Sunday in April and stayed that way until the last Sunday in October, but a change was made in part to allow children to trick-or-treat in more daylight.

In the United States, Daylight Saving Time lasts a total of 34 weeks, lasting from early to mid-March to early November in states where it is in effect.

Some people like to credit Benjamin Franklin as the inventor of daylight saving time when he wrote in a 1784 essay about saving candles: “Early to bed and early to rise makes a man healthy, wealthy and wise.” But that was more of a satire as a serious consideration.

Germany was the first country to introduce daylight saving time on May 1, 1916 during World War I to save fuel. The rest of Europe soon followed.

The USA did not introduce daylight saving time until March 19, 1918. It was unpopular and was abolished after the First World War.

On February 9, 1942, Franklin Roosevelt instituted year-round daylight saving time, which he called “War Time.” This lasted until September 30, 1945.

Daylight saving time did not become standard in the United States until the passage of the Uniform Time Act of 1966, which mandated standard time throughout the country within established time zones. This stipulated that the clocks would be set forward one hour at 2 a.m. on the last Sunday in April and set back one hour at 2 a.m. on the last Sunday in October.

States could still opt out of Daylight Saving Time as long as the entire state did so. In the 1970s, due to the 1973 oil embargo, Congress implemented a trial period of year-round daylight saving time from January 1974 to April 1975 to save energy.

When will daylight saving time resume?

In 2025, daylight saving time will be reintroduced on March 9th and the clocks will then be set forward.

Which states observe daylight saving time?

Almost all US states observe daylight saving time, except Arizona (although some Native American tribes observe daylight saving time in their territories) and Hawaii. U.S. territories, including Puerto Rico, American Samoa, Guam and the U.S. Virgin Islands, do not observe Daylight Saving Time.