(based on the 2011 Rules of Hockey)
Hockey, or Field Hockey as it is known in some parts of the world, is a stick and ball game with origins dating back thousands of years. It is traditionally played on grass, but more often these days - especially at the top levels and in certain countries - hockey is played on synthetic surfaces.
Two teams compete against each other using their 'hooked' sticks to hit, push, pass and dribble a small, hard, usually white, ball, with one aim in mind - to score by getting the ball into the opponents' goal.
To do that, they have to get the ball past the other team's goalkeeper, who protects the goal, and logically, tries to keep the ball out!
There are 11 players on the pitch although each team can have up to five substitutes waiting on the side-line. Players on and off the pitch substitute virtually at any time and can go on and off the pitch any number of times.
As already mentioned, every team must have a goalkeeper - although, very occasionally, a team will play only with field players perhaps so they can put more players into attack. The 10 players other than the goalkeeper are referred to as 'field players', and are dispersed over the field of play. The field players can be put into three general categories - attackers, midfielders and defenders. While no player (other than the goalkeeper) has an exclusively defined role, the attackers are generally on attack, the defenders are generally on defence, and the midfielders do a bit of both!
An essential skill necessary for playing hockey is the ability to control, pass, push, stop and shoot the ball with your hockey stick. This is known as stick work, or stick handling and keeping the ball under close control is called dribbling. It is both beautiful and impressive to watch a player with good stick handling skills control the ball while sprinting the length of the field, or weave through the sticks and legs of defenders to create a chance for shooting at the goal.
It is important to know that the head of a hockey stick has a rounded side (the right-hand side) and a flat side (the left-hand side). It is only with the flat, left-hand, side of the stick and the edges of that side which can be used to play the ball.
It may seem like common sense, but it is worth mentioning that in hockey, field players are not allowed to use their feet (or any other parts of their bodies for that matter) to control the ball. Only the goalkeeper is allowed to use hands, feet, etc. to stop or propel the ball when defending in his or her own circle.
Ball in the air
In general play, the ball must not be raised into the air when hit. It can though be raised by using a scooping or long pushing action of the stick. However, a player will be penalised if they lift the ball in a way which is dangerous to another player.
When the ball is in the air, a player must not play it if it is above shoulder height. A defender (including the goalkeeper) can though use their stick at any height to save a shot at goal - because attackers are allowed to raise the ball in the shooting circle when trying to score a goal. Many shots are raised in one way or another because this is an effective way of scoring goals - and there is more about goal scoring below.
Scoring a goal in hockey is very interesting. There are only certain ways it can be done: from a Field Goal, from a Penalty Corner, and from a Penalty Stroke.
A field goal is a goal scored from open, continuous play. Field goals may only be scored from the 'shooting circle', a roughly semi-circular area in front of the opponents' goal. If an attacker hits the ball from outside the 'shooting circle' and it goes directly into the goal or is only touched by a defender on the way, it does not count as a score.
If a defending team breaks certain rules, the other team may be awarded a 'penalty corner.' It is awarded when a team breaks a rule while defending in their 'shooting circle'. It can also be awarded when a defender is guilty of a particularly bad foul inside the defending quarter of the field - the area enclosed by a line 23 metres from each end of the field.
To take a penalty corner, play is stopped to allow the teams to take their positions in attack and defence. One attacker stands with the ball on a designated spot on the back-line (the line which marks the shorter boundary of the field of play and on which the goal is placed). This player will 'push out' the ball to other attackers, waiting to take a shot at goal. The other attackers usually wait at the top of the shooting circle to receive the ball. But in any case, all attackers have to be outside the shooting circle until the penalty corner begins.
Up to five defenders (including the goalkeeper) position themselves behind the back-line (either inside or outside of the goal) to defend against the penalty corner. The rest of the defenders must stay behind the centre line until the 'push out' has been taken.
The ball is 'pushed out' to one of the attackers waiting to receive it. Before a shot on goal can be taken, the ball must first travel outside the circle. The receiver then usually pushes it back into the circle for a shot either by her/himself or by another attacker.
If the first shot is a hit (as opposed to other types of shots, like a 'flick' or a 'scoop'), the ball must enter the goal at a height of no more than 460mm (or about 18 inches). It is usually pretty easy to tell if the ball is at the right height because the board at the back of the goal is the same height. When a goal is successfully scored, there is a familiar sound of the ball hitting the board, usually followed by players celebrating!
If the first shot is a 'scoop' or a 'flick' - shots that are lifted into the air with a long scooping or pushing action of the stick - then the ball can cross the goal-line at any height, as long as it is not dangerous play.
Once the attacker on the back-line begins to push the ball out, the defenders on the back line may move into the circle, and do their best to stop the other team from scoring.
This a long explanation, but in practice, it all happens very quickly, and is exciting to watch!
A penalty stroke may be awarded for a few reasons, the most common being an offence by a defender in the circle which has probably prevented a goal being scored.
In a penalty stroke, a shot is taken on goal by a chosen player and defended only by the goalkeeper. The shot is taken from a spot 6.4 meters (7 yards) directly in front of the goal. All other players must stand outside the circle, about 23 metres/25 yards away. Match time is stopped while a penalty stroke is being taken.
For general offences throughout the main part of the pitch, a free hit is given against the team which fouled. Common fouls are obstructing an opponent from playing the ball, interfering with the stick or body when tackling, kicking the ball and playing the ball dangerously.
For a free hit, opponents are given the ball where the offence took place. The ball is initially stationary and play will often be re-started by passing the ball to a teammate nearby while all opponents have to be 5 metres away. However, the player taking the free hit can also begin to dribble the ball her/himself.
Special rules apply to a free hit taken by the attacking team inside the 23 metres area they are attacking. All players must start off 5 metres from the free hit and the ball must not be played directly into the circle.
Duration of a match
A regulation length hockey match lasts 70 minutes - which is broken into two halves of 35 minutes each with an interval of between 5 and 10 minutes.
The team with the most goals at the end of the 70 minutes is the winner. It is also possible for a match to end in a draw (or tie). But in some matches - such as during the Hockey World Cup or Olympics, or in a championship game - there must be a winner. In those cases, a match which is tied at the end of regulation time, then goes into extra time (the first team to score in extra time wins), and if necessary, to a penalty stroke competition.
Each match is controlled by two umpires – they are called umpires in hockey but have the same sort of job as referees in many other sports. Basically, each umpire controls half of the pitch although they work cooperatively in the middle part of the pitch.
For bad or repeated offences by players, an umpire can show them a card. A green card is a warning – essentially telling a player not to do that again! A yellow card means the player is suspended from the game for a minimum of 5 minutes or whatever time the umpire decides depending on the nature of the offence. A red card is for a very serious offence and means the player is suspended for the remainder of the match. If a player is suspended temporarily or permanently, their team plays with fewer players.
At world level competitions where the facilities are available, a team playing or the umpires themselves can refer a decision to the video umpire who can use slow motion replays to advise the umpires on the pitch of the correct decision.