As you know, our planet Earth is constantly rotating and has a diameter of 12,742 kilometers and a surface area of 510 million square kilometers. So that entails some consequences.
Such characteristics of our planet determine time difference in various places of the Earth. For example, there is daytime in one part of the world, while there is a night in the other one.
A country with a relatively small area would probably have a single timezone, which means a uniform standard time all over the country. Large countries generally have several time zones established in order not to get people confused.
In order to create a uniform system of time determination, our planet was figuratively divided into 24 sectors – 24 time zones.
There are six continents on the planet Earth:
Nowadays exact time is regulated by Coordinated Universal Time (UTC). Coordinated Universal Time was introduced instead of Greenwich Mean Time (GMT).
There are 24 time zones in the world, which have offsets ahead or behind UTC. For example:
It is important to note that UTC doesn’t change with a change of seasons. But if a time zone observes daylight saving time (or summer time), UTC time offset in summer would be different from UTC time offset in winter.
When daylight saving time is applied, local time changes.
Each country or region may switch to daylight saving at a different time.