It is legally recognized that time is divided into years, months, weeks, days, hours, minutes, and seconds. The time kept by a municipality is known as civic time. A local government may not use a system of time different from that adopted by its state legislature. During daylight saving time, the customary time system is advanced one hour to take advantage of the longer periods of daylight during the summer months.
In the past, the states followed various standards of time until the railroads of the nation cooperated in establishing a standard time zone system, which was then adopted by federal statutes. Under the standard time zone system, the continental United States is divided into four different zones. The time in each zone is based upon the mean solar time at a specified degree of longitude west from Greenwich, England. Eastern standard time is based on the mean solar time at 75° longitude west; Central standard time, on 90° longitude west; Mountain time, on 105° longitude west; and Pacific time on 120° longitude west.
A year is the period during which the earth revolves around the sun. A calendar year is 365 days, except for every fourth year, which is 366 days. The year is divided into twelve months. A week ordinarily means seven consecutive days, either beginning with no particular day, or from a Sunday through the following Saturday. A day is twenty-four hours, extending from midnight to midnight. When distinguished from night, however, a day refers to the period from sunrise to sunset.
In calculating a specified number of days, it is customary to exclude the first and include the last. As a consequence, when a lease provides that it shall continue for a specified period from a particular day, that day is excluded in...