Energy Information Administration
Wind is moving air. Warm air rises, and cool air comes in to take its place. This movement creates different pressures in the atmosphere which creates the winds around the globe. Since the Earth spins, the winds try to move to the right in the Northern Hemisphere, and to the left in the Southern Hemisphere. This is called the Coriolis Effect .
The prevailing wind is a type of wind that usually blows in a region. There are a series of bands around the globe that have steadily blowing prevailing winds near the surface. Different prevailing winds have different names. Trade winds are steady and flow towards the equator. Jet streams are narrow zones of very strong winds in the upper troposphere.
Winds move at different speeds and have different names based on the Beaufort Scale. This scale is shown by numbers from 0 to 12 which goes from calm air to breezes to strong winds or gales . Winds are also grouped by their direction. Easterly winds blow from east to west, while westerly winds blow from west to east.
The fastest recorded wind speed, 230 miles per hour (370 kilometers per hour), was recorded in New Hampshire in 1934, although winds are faster in tornadoes. The windiest place in the world is in Antarctica.
source: windows to the universe