Cricket Fielding Positions
Since there are only 11 players on a team, one of whom is the bowler, and usually another as the wicket-keeper, at most nine other fielding positions can be used at any given time.
Which positions are filled by players and which remain vacant is a tactical decision made by the captain of the fielding team. The captain (usually in consultation with the bowler and sometimes other members of the team) may move players between fielding positions at any time except when a bowler is in the act of bowling to a batsman.
There are a number of named basic fielding positions, some of which are employed very commonly and others that are used less often. However, fielding positions are not fixed, and fielders can be placed in positions that differ from the basic positions.
Most of the positions are named roughly according to a system of polar coordinates - one word (leg, cover, mid-wicket) specifies the angle from the batsman, and is optionally preceded by an adjective describing the distance from the batsman (silly, short, deep or long). Words such as "backward", "forward", or "square" can further indicate the angle.
The image below shows the location of most of the named fielding positions. This image assumes the batsman is right-handed. The area to the left of a right-handed batsman (from the batsman's point of view) is called the leg side or on side, while that to the right is the off side.
If the batsman is left-handed, the leg and off sides are reversed and the fielding positions are a mirror image of those shown.
Some fielding positions are used offensively. That is, players are put there with the main aim being to catch out the batsman rather than to stop or slow down the scoring of runs.
These positions include Slip (often there are multiple slips next to each other, designated First slip, Second slip, Third slip, etc, numbered outwards from the wicket-keeper) meant to catch balls that just edge off the bat; Fly slip; Gully; Leg slip; Leg gully; the short and silly positions.
Bat pad is a position specifically intended to catch balls that unintentionally strike the bat and leg pad, and thus end up only a metre or two to the leg side.
Long stop - who stands behind the wicket-keeper towards the boundary (usually when a wicket-keeper is believed to be inept and almost never seen in professional cricket). This position is sometimes euphemistically referred to as very fine leg.
Sweeper - an alternative name for deep cover, deep extra cover or deep midwicket (that is, near the boundary on the off side or the on side), usually defensive and intended to prevent a four being scored.
Cow corner - an informal jocular term for the position on the boundary between deep midwicket and long on.
Also the bowler, after delivering the ball, must avoid running on the pitch so usually ends up fielding near silly mid on or silly mid off, but somewhat closer to the pitch.
Deep, long - Farther away from the batsman.
Short - Closer to the batsman.
Silly - Very close to the batsman.
Square - Somewhere along an imaginary extension of the popping crease.
Fine - Closer to an extension of an imaginary line along the middle of the pitch bisecting the stumps.
Wide - Further from an extension of an imaginary line along the middle of the pitch bisecting the stumps.
Forward - In front of square; further towards the end occupied by the bowler and further away from the end occupied by the batsman on strike.
Backward - Behind square; further towards the end occupied by the batsman on strike and further away from the end occupied by the bowler.
Additionally, commentators or spectators discussing the details of field placement will often use descriptive phrases such as "gully is a bit wider than normal" or "mid off is standing too deep, he should come in shorter".