While in the autumn, the clocks "fall back" an hour, in the spring time they "spring forward" an hour to make up the difference. This unfortunately means that you'll have one less hour of sleep on the night of Mar. 11. Devices like iPhones, computers, and any other internet-enabled gadget will likely make the switch automatically, but if you rely on a manual alarm clock to wake up in the morning you might need to leave yourself a reminder to change the time.
Normally, the beginning of Daylight Saving Time is a bittersweet gift for people, as it means the sun stays up longer and makes the evening commute a bit less dreary, but also robs you of an hour of sleep. This year, it might not be such a hard pill to swallow, as March 11 is a Sunday. Those that don't work on weekends can sleep in for an extra hour without noticing a difference. Otherwise, get your coffee maker ready.
Daylight Saving Time is a holdover from the days when agriculture was the dominant industry. It came into common practice in 1895, beginning in Germany and other European countries before spreading to the U.S. It's meant to extend daylight hours where people can work outside, at the expense of an impractically early sunrise.
Surprisingly, not all countries use daylight saving time, so international corporations need to make considerations when dealing with affiliates in other places. Areas near the equator have little noticeable difference in sunrise time, so they don't bother with daylight saving time. Brazil, for example, only observes the phenomenon in southern parts of the country, while those who live closer to the Earth's middle don't bother with changing their clocks.
If you've been counting the days down until daylight saving time begins, enjoy it while you can. In 2018, it will come to an end in early November, with no consolation prize but an extra hour of sleep.