Until a little over a hundred years ago, each city in the world set its clocks to local time. Local time was considered to be noon when the sun was at its highest in the sky, when viewed from that particular city. Even cities that neighbored each other set their clocks differently to make this work. For example, if it were 6:00PM in New York City , it would be 6:12PM in Boston , because Boston is about 3 degrees east of New York City . Before modern transportation and communication, this small difference in time between neighboring cities did not matter, and the system worked perfectly well. However, once railroads were built and became popular, this system proved to be both awkward and inefficient.
The Canadian railway planner and engineer Sir Sandford Fleming, along with the railroad companies, first thought of the idea of time zones in the late 1870s. There was a need for them, in order to standardize their schedules; therefore, the railroad companies developed and used them for the first time in 1883. The idea soon caught on and in 1884, at an International conference in Washington, D.C. , world time zones were determined. The world was divided into 24 time zones, each one a long strip from North Pole to South Pole, about 15 degrees of longitude wide and about one hour difference in time. Everyone that resides in one time zone would set his or her clock the same way, to the local time in the center of the time zone.
Since there are 24 hours in a day, dividing the earth into 24 time zones meant that everybody was using a time setting very close to their local time. Because each time zone differed by a whole number, it was easy to convert from the time in one zone to the time in another, and therefore easier to make travel plans. Today, this time zone system is still in use in most countries in the world, with only a few places setting their closet 15 or 30 minutes different from the time according to the standardized time zone system.
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