In the sport of cricket there are two broad categories of bowlers: pace and spin. Pace bowlers rely mostly on the speed of the ball to dismiss batsmen, whereas spin bowlers rely on the rotation and turn of the ball. Pace bowlers Pace bowlers, or fast bowlers or pacemen, rely on speed to get a batsman out. This type of bowler can be further classified according to the speed at which they bowl the ball on average. Most pace bowlers are medium-fast to fast in top level cricket. In general, bowlers of this type are described as right arm or left arm "fast" or "fast-medium". Another technique of fast bowling is the sling action. This action generates extra speed but sacrifices control. Exponents include Waqar Younis, Lasith Malinga, Mitchell Johnson, Fidel Edwards and Shaun Tait. Though there may have been faster balls bowled, the highest electronically measured speed (after speed guns became popular) for a ball bowled by any bowler is 161.3 km/h (100.23 mph) by Shoaib Akhtar (Pakistan) against England on 22 February 2003 in a World Cup match at Newlands, Cape Town, South Africa. Swing bowlers Swing bowlers are pace bowlers who, apart from being fast, also use the seam of the ball to make it travel in a curved path through the air. This is further encouraged by systematically polishing one side of the ball while allowing the other side to become roughened and worn. The differing airflow around the two sides will cause the ball to swing in the air, towards the roughened side. By changing the orientation of the ball in his hand, a bowler may therefore cause the ball to swing into or away from the batsman. In addition to a well-polished ball, other factors help the ball to swing, notably damp or humid weather conditions. However balls which have been in play for some time do not tend to swing so much due to the deterioration of the seam. In addition, bowlers of express pace do not tend to get as much swing as the fast-medium-to-medium pace bowlers. Reverse Swing as the name suggests, moves in the opposite direction to conventional swing. Instead of the ball drifting towards its rougher side, it veers towards the smooth. Typically, a ball needs to be older, and thoroughly knocked about, before it arrives in “the zone” to reverse; and it takes a faster bowler to inject