CSTEI

Before time zones were set up, there was a great deal of confusion, especially when people had to use railroad timetables. To end this confusion the untied states in 1883 began using a system of standard time zones. In 1884 an international conference was held in Washington, D.C., to set up a system to fit the whole world. The earth was divided into 24 zones, each covering 15 degrees of longitude. This is a natural division, for the earth rotates at the rate of 15 degrees each hour. Greenwich in England is selected as the starting point. Time is the same in each zone and time difference between each time zone is an hour.