Time zones are created to account for the Earth's rotation and to keep track of different times in different parts of the world. This is necessary because the Earth's rotation causes the sun to appear to move across the sky at different times in different locations.

There are 24 time zones in the world, each representing a 15-degree segment of longitude. This means that there is a one-hour difference in time between each time zone.

The Prime Meridian is the line of longitude that runs through Greenwich, England. It is used as the reference point for measuring longitude, and all other longitudes are measured east or west of the Prime Meridian.

The International Date Line is the line of longitude that runs through the center of the Pacific Ocean. It is the line where the date changes from one day to the next. When you cross the International Date Line from east to west, you gain a day. When you cross the International Date Line from west to east, you lose a day.

Standard time is the time that is used during the winter months, while daylight saving time is the time that is used during the summer months. Daylight saving time is typically one hour ahead of standard time.

Russia has the most time zones, with 11 time zones in total.

Vatican City has the fewest time zones, with only one time zone.

The time difference between New York City and London is 5 hours.

The time difference between Tokyo and Sydney is 1 hour.

The time difference between Los Angeles and Beijing is 16 hours.

The time difference between Moscow and Cairo is 2 hours.

The time difference between Santiago and Buenos Aires is 1 hour.

The time difference between Auckland and Wellington is 1 hour.

The time difference between Honolulu and Anchorage is 2 hours.

The time difference between Reykjavik and Dublin is 1 hour.