Windsurfing (also called Boardsailing) is a hybrid of Surfing and Sailing; using a small board of between 2 and 4.7 metres, which is powered by wind acting on a single sail connected to the board via a flexible joint.

This sail board is the most minimalistic version of the modern sailboat - with the major exception being that steering is accomplished by the windsurfer tilting the mast and sail, or when planing by banking the windsurfing board rather than using a rudder.

Shortboards, under 3 metres in length, are the most commonly used boards today. They are designed to be used primarily in planing mode - where the board is sliding over the surface of the water rather than cutting through it. Planing is faster and gives more manoeuvrability, but requires a different technique from the water-displacing cutting technique.

There are several types of Windsurfing board. These can be divided into amateur such as Freeride and Wave Boards, or Competition boards. Competition boards are either designed for speed, such as Racing Boards, or for tricks such as Freestyle Boards. Currently, two designs of a sail predominate: camber induced and RAF (Rotating Asymmetric Foil). The current trend is that racier sails have camber inducers while wave sails and most recreational sails do not.