US time

On March 11, 1918, the Standard Time Act established time zones for the United States. This act divided the country into four time zones: Eastern, Central, Mountain, and Pacific.
Alaska and Hawaii were not included in the original act, but they were later added to the time zone system. Alaska is in the Alaska Time Zone, and Hawaii is in the Hawaii-Aleutian Time Zone.
The United States also observes daylight saving time, which begins on the second Sunday of March and ends on the first Sunday of November. During daylight saving time, clocks are set forward one hour.
The time zones in the United States are as follows:
* Eastern Time Zone (ET): UTC-5
* Central Time Zone (CT): UTC-6
* Mountain Time Zone (MT): UTC-7
* Pacific Time Zone (PT): UTC-8
* Alaska Time Zone (AKST): UTC-9
* Hawaii-Aleutian Time Zone (HST): UTC-10
The United States is a large country, and the time zones reflect the different geographic regions of the country. The Eastern Time Zone is the most populous time zone, and it includes the cities of New York, Philadelphia, and Washington, D.C. The Central Time Zone includes the cities of Chicago, Dallas, and Houston. The Mountain Time Zone includes the cities of Denver, Phoenix, and Salt Lake City. The Pacific Time Zone includes the cities of Los Angeles, San Francisco, and Seattle.
The time zones in the United States are important for a number of reasons. They help to ensure that people are working and sleeping at the same time, and they help to coordinate transportation and other activities. The time zones also help to prevent confusion when people are traveling across the country.