The prevailing winds are different as you move from the North Pole to the South Pole.  Up in the north where I am we have the westerlies.  Which means that the prevailing winds blow from the west eastward.  Further south, roughly around the lattitude of the Gulf of Mexico, the winds blow in the opposite direction, from the east downward towards the equator in a southwest direction.  Below the equator the winds blow from the west in a northeast direction towards the equator.  Further south, the winds blow from east to west.

Prevailing winds are a strong consideration when you’re planning east-west travel as it will slow down the trip and burn more fuel as you fight the winds.  Going west to east will shorten the trip and save on fuel.  These are factors in flying, but also in sailing.  Adding to the economy in my lattitude on an east-west trip is the Gulf Stream ocean current.

Prevailing winds also factor into other things.  You don’t want to be downwind of a sewage treatment plant.  Or in my case a next-door neighbor who chain smokes.  Important considerations like these require a sense of place, an understanding of the prevailing winds, and foresight into who is moving next to you.