Spring forward, fall back.

That's the easy way to remember what you're supposed to do when Daylight Saving Time starts and ends.

At 2AM on the second Sunday in March, we "spring forward" an hour.

At 2AM on the first Sunday in November, we'll "fall back."

This year, Daylight Saving Time begins in the United States at 2AM on Sunday, March 8th.

The only states that do not observe Daylight Saving Time are Arizona and Hawaii. Puerto Rico, the US Virgin Islands, Guam and American Samoa don't observe it either.

What's the reason for Daylight Saving Time?

To get more hours of sunlight when people are awake to take advantage of it.

Without Daylight Saving Time, the sun would come up as early as 4AM during the summer in some parts of the country. Unless you're really a morning person, you might miss several hours of daylight.

There's also a more practical reason for Daylight Saving Time: If it stays lighter later, you don't have to turn on the lights inside your home until later.

Studies have actually shown that Daylight Saving Time helps people use less energy. Not only is that good for the environment; it also saves money.

So who came up with the idea of Daylight Saving Time?

Benjamin Franklin, according to the historians, way back in the 1700's!

Back then, every single city had its own time. Basically, when the sun was at its highest point, it was noon.

That made it simple to tell time if you were always in one place. But what if you were traveling? The time in New York City was different from the time in Philadelphia and both of those times were different from the time in Boston.

The United States didn't even accept the concept of Standard Time until 1883 - and only then because the railroads needed it to figure out their schedules properly.

That year, most of the country was divided into four time zones - Eastern, Central, Mountain and Pacific. Eastern Standard Time is one hour ahead of Central, two hours ahead of Mountain and three hours ahead of Pacific. (Alaska and Hawaii are in other time zones).

But it still took nearly a century to get things fully standardized. And local communities continued to set their clocks according to their own calculations.

The United States did not observe Daylight Saving Time until 1918. The first period of Daylight Saving Time began on March 31st of that year and lasted seven months.

There was also Daylight Saving Time the following year. But according to historians, the idea was so unpopular at the time that Congress repealed it.

Some states and cities continued to observe Daylight Saving Time anyway. But that just made the nation an even more confusing mishmash of different time zones.

During World War II, President Franklin D. Roosevelt ordered year-round Daylight Saving Time from February 9, 1942 to September 30, 1945. The goal was to get people to save energy so there would be more for the war effort.

Aside from that period, federal Daylight Saving Time did not return until 1966. That's when President Lyndon B. Johnson signed the Uniform Time Act.

The dates have changed periodically since then. But Daylight Saving Time always starts around the beginning of spring (give or take a few weeks) and ends in early fall.

So remind your parents to turn their clocks forward before they go to bed Saturday night. Otherwise, you'll be late for school on Monday.