Daylight saving is a means of getting more light out of the day by advancing clocks by one hour during the summer. This way, sunrise is one hour later in the morning, when most people are usually asleep anyway, and sunset is one hour later in the evening.

To further maximize energy savings, starting in 2007, Congress changed the start and finish of daylight saving time from the first Sunday in April through the last Sunday in October to the second Sunday in March through the first Sunday in November.