Bowling action
In the sport of cricket, the bowling action is the set of movements that result in the bowler releasing the ball in the direction of the batsman. The bowling action can be broken down into a number of parts: There are certain principles that apply to all parts of the bowling action, such as balance, athleticism and keeping the movement flowing in a narrow corridor directed towards the batsman. Coaching books describe idealised bowling actions. But good coaches are well aware that many successful bowlers employ their own unique styles and some give birth to new, improved technique  (for example, Bart King). The above links all describe the most commonly taught techniques. Approach. The approach is the motion of the bowler prior to bowling the ball. It is also known as the run-up. A spinner's approach differs from that of a medium pace or fast bowler, but certain principles remain the same: The strides of the bound, back foot contact, front foot contact and the first stride of the follow through should all be in line to give a balanced action that flows towards the target. Medium pace and quick bowlers usually employ a straight approach  that is aligned toward the target. Spin bowlers, on the other hand, tend to have more varied approaches. Other recommended elements of the approach are: Bound. The bound is a jump that allows the bowler to transition from the run-up to the back foot contact position. For a chest on bowler not much transition is needed. So, many chest on bowlers have a low, short bound. In contrast, side on bowlers need to rotate their bodies through ninety degrees and so tend to have a longer, higher bound. A high bound can lead to the knee on the back  foot collapsing and so lose momentum. Delivery stride. Delivery stride is the stride during which the delivery swing is made, whether the ball is released or not. It starts when the bowler's back foot lands for that stride and ends when the front foot lands in the same stride. Back foot contact. Back foot contact is position of the bowler at the instant when the back foot lands on the ground just prior to delivering the ball. For a right-handed bowler, the back foot is normally the right foot. An alternative name for back foot contact is "coil . To avoid back injury it is important that the hips and shoulders are aligned at back foot contact. This can be done in any of the following positions: An action that fails to align hips and shoulders at back foot contact is termed a mixed action". Front foot contact. Front foot contact is the position of the bowler at the moment when the front foot hits the ground just prior to delivering the ball. For a right-handed bowler the front foot is normally the left foot. Point of release. The point of release is the position of the ball  in relation to the body at the moment when the ball is released. It is crucial for the arm to be stiff, not bent, and the wrist rather looser, to ensure smooth release of the ball, and sufficient bounce off the pitch. Otherwise, the action will resemble chucking. The left shoulder ought to be somewhat towards the stumps, the arm beside the bowler falling away, having just before this stage been pointing directly at the stumps. For fast bowlers at the point of release the back of hand will be facing in the opposite direction of the batsmen facing the  pending delivery. The front of the upright wrist and tips of the index and middle fingers all point to the target. For spin bowlers the wrist may well be at various angles at release point. This is because one is trying to create drag on a particular side of the ball, not propel it straight as per the section above. Follow through. The follow through is the motion of the bowler after releasing the ball.