The game is played in accordance with 42 laws, which have been developed by the Marylebone Cricket Club in discussion with the main cricketing nations. Teams may agree before a game to introduce other rules or alter some of the existing rules. In particular, there are a number of modifications to rules dictating fielding positions for professional limited overs matches.
Players
A team consists of eleven players. Depending on his or her primary skills, a player may be classified as a specialist batsman or bowler. A balanced team usually has five or six specialist batsmen and four or five specialist bowlers. Teams nearly always include a specialist wicket-keeper because of the importance of this fielding position. Each team is headed by a captain, who is responsible for making tactical decisions such as determining the batting order, the placement of fielders and the rotation of bowlers.
All rounder
A player who excels in both batting and bowling is known as an all-rounder. One who excels as a batsman and wicket-keeper is known as a "wicket-keeper/batsman", sometimes regarded as a type of all-rounder. True all-rounders are rare; most players focus on either batting or bowling skills.
Umpires
Two on-field umpires preside over a match. One umpire stands behind the bowler's wicket, and adjudicates on most decisions. The other (the "square leg umpire") stands with a side view of the batsman (usually near the fielding position called square leg), and assists in decisions for which he or she has a better view. In some professional matches the facility exists for them to refer some decisions to a third umpire, who has the assistance of television replays. In international matches a match referee ensures that play is within the laws of cricket and the spirit of the game. The third umpire and referee do not take the field during play.
The playing field 
The cricket field consists of a large, often circular or oval-shaped, grassy ground. There are no fixed dimensions for the field but its diameter usually varies between 450 feet (137 m) and 500 feet (150 m). The perimeter of the field, known as the boundary, is marked, often with a rope or a painted line.
A wicket consists of three stumps that are hammered into the ground, and topped with two bails.
Most of the action takes place in the centre of this ground, on a rectangular clay strip usually with short grass called the pitch. The pitch measures 10 × 66 feet (3.05 × 20.12 m). The longer dimension of the pitch is also a unit of length known as a chain.
At each end of the pitch three upright wooden stakes, called the stumps, are hammered into the ground. Two wooden crosspieces, known as the bails, sit in grooves atop the stumps, linking each to its neighbour. Each set of three stumps and two bails is collectively known as a wicket. One end of the pitch is designated the "batting end" where the batsman stands and the other is designated the "bowling end" where the bowler runs in to bowl.
The area of the field on the side of the line joining the wickets where the batsman holds his bat (the right-hand side for a right-handed batsman, the left for a left-hander) is known as the "off side", the other as the "leg side" or "on side".
Lines drawn or painted on the pitch are known as creases. Creases are used to adjudicate the dismissals of batsmen and to determine whether a delivery is legal.
The nature of the pitch
Pitches vary in consistency, and thus in the amount of bounce, spin, and seam movement available to the bowler. Hard pitches are usually good to bat on because of high but even bounce. Dry pitches tend to deteriorate for batting as cracks often appear, and when this happens spinners can play a major role. Damp pitches, or pitches covered in grass (termed "green" pitches), allow good fast bowlers to extract extra bounce and seam movement. Such pitches tend to offer help to fast bowlers throughout the match, but become better for batting as the game goes on.
A typical cricket field.
Batting
The batsman may play a "shot" or "stroke", attempting to hit the bowled ball with the flat surface of the bat. If the ball brushes the side of the bat it is called an "edge". There is no requirement for the batsman to play a shot, and there is no requirement to run if the ball is struck. The batsman automatically scores runs if he hits the ball to the boundary. Shots are named according to the style of swing and the direction aimed. As part of the team's strategy, the player may bat defensively, blocking the ball downwards, or aggressively, hitting the ball hard to empty spaces in order to score runs.
Batsmen come in to bat in a batting order, decided by the team captain. The first two batsmen - the "openers" - usually face the most hostile bowling, from fresh fast bowlers with a new ball. The top batting positions are usually given to the most competent batsmen in the team, and the non-batsmen typically bat last. The batting order is not agreed beforehand, and if a wicket falls any player who has not batted yet may bat next.
Run scoring
To score a run, a striker must run to the opposite end of the pitch, while his non-striking partner runs to his end. To register a run, both runners must touch the ground behind the crease with either their bats or their bodies (the batsmen carry their bats as they run). If the striker hits the ball well enough, the batsmen may double back to score two or more runs. However, no rule requires the batsman to run upon striking the ball. The decision to attempt a run is ideally made by the batsman who has the better view of the ball's position, and this is communicated by calling: "yes", "no" and "wait" are often heard. The batsmen swap ends every time an odd number of runs are scored.
If a fielder knocks the bails off the stumps with the ball while no part of the batsman is grounded behind the popping crease, the batsman nearer the broken wicket is run out. The batsman may ground the bat, provided he or she is holding it.
If the ball reaches the boundary, then runs are automatically scored: six if the ball goes over the boundary without touching the ground, four if it touched the ground. These are scored instead of any runs the batsmen may have already run (unless they have run more, which is unlikely), and they return to the ends at which they started.
Bowling
A bowler delivers the ball toward the batsmen: during the bowling action the elbow may be held at any angle and may bend further, but may not straighten out. If the elbow straightens illegally then the square-leg umpire may call no-ball. The current laws allow a bowler to straighten his arm 15 degrees or less.
The bowler's primary goal is usually to get the batsman out; the most common modes of dismissal (except run out) are credited to the bowler, who is said to have taken a wicket. Dismissing an accomplished batsman is more difficult than dismissing a non-batsman. The bowler's secondary task is usually to limit the numbers of runs scored. Occasionally the match situation makes it more important to limit runs than take wickets.
There are many types of bowler, and many nuances of bowling techniques. Two categories are pace bowlers, who aim to bowl quicker than the batsman's reaction speed, and spin bowlers who bowl slower deliveries that bounce and curve in unpredictable ways.
