The pattern or sequence of motions performed during a forehand or backhand stroke is called technique. The motions that produce a specific technique are the result of the internal and external forces acting on a player's body. Coaches as well as athletes need to understand what these forces are and how they are related to the performance of tennis strokes. A good understanding of these biomechanical principles will help coaches to better analyse and improve athletic performance and to determine why certain movements or techniques are better than others. The purposes of this paper are to explain the basic biomechanical principles used to develop explosive forehand and backhand strokes and to review the latest biomechanical research available on the forehand and backhand strokes.