A time zone is a region of the globe that observes a uniform standard time for legal, commercial, and social purposes. Time zones tend to follow the boundaries of countries and their subdivisions instead of longitude.
Most of the time zones on land are balance from Coordinated Universal Time (UTC) by a whole number of hours (UTC−12:00 to UTC+14:00), but a few zones are offset by 30 or 45 minutes (e.g. Newfoundland Standard Time is UTC−03:30, Nepal Standard Time is UTC+05:45, Indian Standard Time is UTC+05:30 and Myanmar Standard Time is UTC+06:30).
Some higher latitude and temperate zone countries use daylight saving time for part of the year, typically by adjusting local clock time by an hour.
The first known person to conceive of a worldwide system of time zones was the Italian mathematician Quirico Filopanti. He introduced the idea in his book Miranda! published in 1858. He proposed 24 hourly time zones, which he called “longitudinal days”, the first centered on the meridian of Rome. He also proposed a universal time to be used in astronomy and telegraphy. But his book attracted no attention until long after his death.
If you travel, you know how much of an inconvenience it is to have to remember to adjust your watch and the clock on your laptop computer to reflect the local time at your destination, and then remember to switch it back when you return.
Time zones, which are supposed to keep our clocks consistent with the solar time wherever we are on the planet, can really be difficult sometimes when you are traveling across multiple time zones.
As you move even a short distance from one spot to another across the planet, for most of human history, the time of day differs everywhere. It’s strange to think that time zones were invented as a way of reducing confusion rather than causing it.
WHY WE HAVE DIFFERENT TIME ZONES
Confusion about time wasn’t a huge problem until the 1800s when railroad trains started making it possible to quickly travel from one place to the next. All of a sudden, “people were missing trains.
A Scottish engineer, Sandford Fleming, missed a train in Ireland in 1876 due to a mistake in a printed timetable and decided to fix things.
Fleming developed a system in which the world was divided into 24 time zones, spaced at 1-degree intervals across the planet. Eventually, the world adopted Fleming’s system, in which time was based not on the local solar day, but upon how many time zones separated a location from the Royal Greenwich Observatory in the U.K.