how many time zones are there in the world?
http://www.answers.com/topic/time-zone
The world is divided into 24 time zones, each covering about 15 degrees longitude.
http://www.worldtimezone.com/
There are a total of 24 time zones in the world. To understand how this is calculated, it is helpful to know that the Earth rotates 360 degrees in 24 hours. This means that for every 15 degrees of longitude (360 divided by 24), we have a time zone.
To determine the time zone of a specific location, you will need to know the longitude of that place. The Prime Meridian, located in Greenwich, London, is considered the starting point for measuring longitudes. The time at this location is known as Greenwich Mean Time (GMT) or Coordinated Universal Time (UTC).
As you move eastward from the Prime Meridian, the time advances by one hour for every 15 degrees. Conversely, as you move westward, the time decreases. This is why time zones to the east of GMT are typically ahead, while those to the west are behind.
It is important to note that some countries or regions may deviate from the standard time zones due to political or geographical reasons. Additionally, some places practice daylight saving time, which temporarily adjusts the local time by one hour to maximize sunlight during specific months of the year.