Introduction

Hockey is the oldest known ball and stick game. Records exist of it having been played in Persia in 2000 BC. In medieval Europe, pictures of men playing a game with hooked sticks appear on stained-glass windows at both the Canterbury and Gloucester cathedrals. It became so popular by the Middle Ages that it was banned in England for a time because it interfered with the practice of archery, which was the basis for national defense. The name hockey probably derives from the French hocquet, or shepherd's crook, and refers to the crooked stick.

Hockey, or field Hockey, is a very popular sport. Men and women, regardless of age, play Hockey for recreational reasons. However, in high-level competition, athletes must develop good physical condition, team spirit and concentration in order to be successful.

A Hockey game is played between two teams, of 11 players each. A game is divided into two 35-minute periods, with a 10-minute interval in between. Each team tries to score as many goals as possible in the opposite team’s goal post.

There are two Hockey disciplines: indoor Hockey, which is held in an indoor venue, and outdoor Hockey, which is held in an outdoor venue. Only outdoor Hockey is included in the Olympic Games competition schedule.

Hockey games are usually conducted on grass. At high-level competitions though, like the Olympic Games, Hockey is played on synthetic surfaces.

Understanding Hockey

Ball

The ball is white, hard and made of Teflon. Its surface has dimples. It weights 156 to 163 g and its circumference varies between 224 and 235 mm.

The Field Hockey Stick

The structure of a field hockey stick can be roughly divided into three sections: the handle, shaft, and toe (or head). The handle or grip of the stick is round, while the shaft and toe have contour. The left side of both the shaft and the toe are flat, while the right side is rounded. Players are only allowed to use the flat side of the stick to play the ball.
Sorry to all you lefties - there are no left-handed sticks.

The common field hockey stick is composed of hard wood, wrapped and reinforced by protective materials such carbon, fiberglass, Kevlar or ceramic. However, also currently becoming popular are composite and semi-composite sticks, either made completely or partially out of synthetic materials.

The length and weight of a field hockey stick depends on the height of the person and also the functionality of the position they play. Also the shape and length of the toe of the stick can vary to certain degrees.

Clothing and gear

The goalkeeper must wear, over any upper body protectors, a shirt of a different colour than the ones worn by his or her teammates and the opposite team's players. The goalkeeper's body protectors consist of the secured protective headgear, leg guards, kickers and hand protectors, all of which must have no rough edges or protrusions. The hand protectors may be no more than 228 mm wide and leg guards no more than 300 mm wide. In general, the clothing and the equipment of the goalkeeper must comply with the rules and regulations of FIH, so the gear will not artificially increase the size of the goalkeeper's body or the area that he or she is capable of protecting.  

Field of Play

The game of field hockey is played on a rectangular field which is 100 yards (91.4 m) long and 60 yards (55 m) wide and is divided by a center line and a 25 yard line in each half of the field. The game is played on both grass fields and on watered down artificial turf (astro) although, for serious play, only astro is used because it is totally flat and obviously far faster than grass. The goal cages are 4 yards/12 feet (3.66 m) wide and 7 feet (2.13 m) high and there is a striking circle measured out 16 yards from each goal post. This striking circle (semi-circle) is also known as 'the circle' or the 'D' and a goal can only be scored from a shot taken within this semi-circle. The ball cannot be lifted into the circle but must be brought in on the ground.

Game Length

A field hockey game consists of two halves of 35 minutes with an intermission of 5-10 minutes. The game is continuous (as in soccer) with no time-outs, until a call by one of the two umpires (there is one umpire for each side of the field) or delay because of an injury. Although goals occur more frequently than in soccer (a game which hockey is sometimes compared with: 'soccer with sticks'), field hockey is usually relatively low scoring.

Team Size/Objective

The game is played by two teams of 11 players - 10 players and 1 goaltender. Although there are set positions (forwards, backs, wings etc.) the composition of any team is at the discretion of the coach (what positions players play at). The object of the game (not that surprisingly) is to have scored more goals than your opponents by the game's end, with one point being awarded for each goal scored as in most games of this nature.

Player Positions

Every team consists of ten field players, who are classified as attackers, midfielders, defenders, and a goalkeeper who remains in his team's shooting circle.

In the Olympic Games, every team is made up of 16 players, 11 of which remain on the field while the other five are interchange players. Although coaches may make unlimited substitutions during a game, they are not permitted to make any substitutions during penalty corners and penalty strokes. In such cases, coaches can only replace injured or suspended goalkeepers.

Scoring a Goal

A field goal is scored after a shot at goal by an attacking player within the defending team's circle passes over the goaline.

Penalty Corner

If a defending team breaks a rule within their own circle, like preventing a goal from being scored with one's body, a penalty corner may be awarded. A penalty corner is executed as follows:

An attacker stands with the ball on a designated spot along the back line and pushes it out to a player waiting outside the circle. At the same time, five defenders who waited behind the back line start running towards the attacker who is about to attempt a goal. The ball must be stopped by an attacking player outside the circle before players can shoot for a goal.

Penalties

Based on the offense, different types of penalties are awarded, such as free hits, penalty corners, and penalty strokes.

If a player violates a rule they may receive a:

Green card: warning,
Yellow card: temporary suspension (a minimum of 5 minutes)
Red card: permanent suspension.

Umpires

Hockey matches are controlled by two umpires. In international matches, umpires appointed to games are from neutral countries. Their role is to ensure fair play and adjudicate on the rules issues. Each umpire covers roughly half the pitch, while around the middle of the field they work together. Signals are used to communicate decisions.

2004 Olympic Hockey Games will be conducted as follow:

Men: Teams will be placed in two pools of six teams for the preliminary rounds. Each team competes against the other teams in that pool.

The top two teams in each pool proceed to the semi-finals. The remaining teams play classification matches for places 5-12.

Semi-final winners compete for the gold and silver medals. Semi-finals losers compete for the bronze.

Women: Teams will be placed in two pools of five teams for the preliminary rounds. Each team competes against the other teams in that pool.

The top two teams in each pool proceed to the semi-finals. The remaining teams play classification matches for places 5-10.

Semi-final winners compete for gold and silver medals. Semi-final losers compete for bronze. 

source: http://www.fieldhockeytournament.com/ thegame/how.html