A delivery or ball in cricket is the single action of bowling a cricket ball toward the batter. Once the ball has been delivered, batters may attempt to score runs, with the bowler and other fielders attempting to stop this by getting the batters out. When the ball becomes dead, the next delivery can begin.

During the play of the game, a member of the fielding team is designated as the bowler and bowls deliveries toward the batter. Six legal balls in a row constitutes an over, after which a different member of the fielding side takes over the role of bowler for the next over. The bowler delivers the ball from their end of the pitch toward the batter standing at the opposite wicket at the other end of the pitch. Bowlers can be either left-handed or right-handed. This approach to their delivery, in addition to their decision of bowling around the wicket (from the sides of the wicket on the bowler's end) or over the wicket, is knowledge of which the umpire and the batter are to be made aware.

Some forms of cricket limit the number of legal deliveries that may be bowled in each innings; for example, 100-ball cricket has a maximum of 200 legal deliveries in the game (unless there is a tie). Every delivery in a cricket match is notated by the number of completed overs that have occurred before that delivery, as well as which delivery in the current over that delivery is; for example, "Over 14.2" indicates that 14 overs have been completed and the second delivery of the 15th over is the one under consideration. Since illegal deliveries do not count towards the progression of an over, a set of consecutive illegal deliveries (and the legal delivery that follows them) will have the same notation. Illegal deliveries usually occur when a bowler bowls from too close to the batter, or delivers the ball out of the batter's reach.

All deliveries are either legal (also known as fair, valid, or "one of the over"), illegal, or in rare circumstances, called dead and invalidated.

An illegal delivery always results in the batting team being awarded one run in addition to any other runs scored off the illegal delivery, does not count towards the completion of an over, and is divided into two categories: wides and no-balls. No-balls are considered a more serious infraction than wides, with the batters being shielded from most methods of dismissal, and in some competitions result in the batting team being awarded two additional runs and/or a "free hit" on the next legal delivery (on a free hit delivery, the batters have the same protections against being dismissed as on a no-ball).

A delivery is called wide if it is so far out of reach of the striker that it can not be hit by the striker through the use of a normal cricket stroke. Note however that a delivery may not be called a wide if the striker changes their positioning before the ball is bowled in such a way that they bring the ball within their reach.

A delivery can be called a no-ball for various reasons, which may pertain either to the actions of the bowler or the other players on the fielding team. The most common reasons a no-ball occurs are because the bowler either fails to keep some part of his front foot behind the popping crease when bowling the ball, or bowls the ball and it reaches the striker above the waist without having bounced before reaching the striker.

Deliveries can be made by fast bowlers or by spin bowlers. Fast bowlers tend to make the ball either move off the pitch (‘seam’) or move through the air (’swing’), while spinners make the ball ’turn’ either toward a right-handed batter (as in the case of off spin and left-arm unorthodox spin) or away from him (as in the case of leg spin and left-arm orthodox spin).