Wind is any current of air. It can be as gentle as a breeze or as destructive as a hurricane. Wind measured on land is given in miles per hour, and wind measure at sea is in knots. The direction of a given wind is determined from the point of the compass from which it blows (for example, northeast, south). In parts of the world, names are given to seasonal winds of particular quality. For example, Santa Ana is a name given to a hot, dry wind that blows from the north or east in southern California.

Wind can be measured using several methods and devices. The Beaufort Wind Scale is a commonly-used numeric scale for specifying the force of the wind used in all parts of the world (both on land and at sea.) It was devised by Admiral Francis Beaufort in 1806 for recording wind force at sea based on the effect of the wind on a full-rigged ship. An anemometer is a device with cups that spin from the force of the wind, and is used for determining wind speed. A weather vane is a lat object that rotates with the wind and shows wind direction. A wind sock is commonly seen at an airport. Wind socks show direction and speed of the wind.