Wind is a mass of air that moves in a mostly horizontal direction from an area of high pressure to an area with low pressure.High winds can be very destructive because they generate pressure against the surface of a structure. The intensity of this pressure is the wind load. The effect of the wind is dependent upon the size and shape of the structure. Calculating wind load is necessary for the design and construction of safer, more wind-resistant buildings and placement of objects such as antennas on top of buildings.