Final answer:
Earth's time zones are based on the rotation of the Earth on its axis, creating variations in daylight and darkness. There are 24 time zones in total, each representing a one-hour difference. The Prime Meridian serves as the starting point for the time zones.
Step-by-step explanation:
Earth's time zones are based on the rotation of the Earth on its axis. The Earth takes approximately 24 hours to complete one full rotation. This rotation causes the different parts of the Earth to experience varying amounts of daylight and darkness. Time zones were created to standardize the measurement of time around the world and to account for these variations in daylight.
There are 24 time zones in total, each representing a one-hour difference. The Prime Meridian, which passes through Greenwich, London, serves as the starting point for the time zones. When it is noon at the Prime Meridian, it is midnight at the International Date Line on the opposite side of the Earth.
For example, when it is noon in New York City (Eastern Standard Time), it is 5 PM in London (Greenwich Mean Time) and 2 AM (the following day) in Sydney, Australia (Australian Eastern Standard Time).
Learn more about Earth's time zones