Do you know how daylight savings time came to be ? Originally .....
During World War I, in an effort to conserve fuel, Germany began observing DST on May 1, 1916. As the war progressed, the rest of Europe adopted DST. The plan was not formally adopted in the United States until the Standard Time Act of March 19, 1918, which established standard time zones and set summer DST to begin on March 31, 1918.
Daylight saving time in the United States is the practice of setting the clock forward by one hour during the warmer part of the year, so that evenings have more daylight and mornings have less. Most areas of the United States currently observe daylight saving time(DST), the exceptions being Arizona (except for the Navajo Nation, which does observe daylight saving time), Hawaii, and the overseas territories of Puerto Rico, American Samoa, Guam, Northern Mariana Islands, and the United States Virgin Islands.
taken from Wikipedia