Although man has probably kicked things around for fun since time immemorial, the modern organized game of soccer (or "football" as it's known in much of the world) sprang from rules codified by England's Football Association in 1863. Since that time, the basic rules and format of the game have remained largely unchanged, although soccer's international governing body, FIFA (Federation Internationale de Football Association) tinkers with a rule or two once in a while.
The rules of soccer are quite simple and relatively few in number, especially when compared to some of the American sports leagues like the National Football League and Major League Baseball. The plain objective of the game is to score a goal by propelling it into the opponent's goal without using the hands or arms. Do this more often than the other team and you win the match.
Each team consists of 11 players, one of them being the goalkeeper, who is the only member of the team allowed to use his hands on the field of play. Ahead of the goalkeeper is a row of 3 or 4 players known as defenders. Depending on the preferred formation of the team, one of them may be a "sweeper" who acts as a utility man who sweeps up defensively behind the defenders when necessary.
In front of the defenders are the midfielders, who act as the liaison between defenders and the attacking forwards on the team. These players have to be versatile enough to track back and help the defense, as well as orchestrate attacking, potential goal-scoring moves with the forwards.
Wide-playing forwards are known as wingers and their job is to play on the flanks and cross the ball into the center of the field to waiting strikers attempting to get into a scoring position. Of course, these strikers do have to contend with the dreaded "offside" rule. This rule was designed to stop attacking players from simply standing around the goalmouth and waiting to poach goals. If an attacking player moves into a position where there are no defenders on the opposing team between himself and the opposing team's goalkeeper, the ball cannot be delivered to him, or the referee will blow the whistle for offside. Offside is a controversial rule in soccer, especially since there are many close judgment calls, and goals are often disallowed if players scoring them are judged to have been in an offside position.
Soccer equipment needs are relatively few, consisting of a leather ball with a circumference of 27 to 28 inches, and weighing between 14 and 16 ounces. Players wear studded soccer shoes (or "cleats" as they are known stateside) and hard plastic protective shinguards are worn beneath the socks.
Of course, you also need a field to play the game on. The field of play in soccer doesn't actually have exact size measurements, but the length is required to be between 100 and 130 yards and the width anywhere between 50 and 100 yards. The all-important netted goals at each end of the field are 8 yards wide and 8 feet tall.
The head official is known as the referee and he works in tandem with two linesmen who closely monitor play from the sidelines. Since the referee can only cover so much ground and may not be able to see everything happening on the field of play, linesmen assist the referee by indicating, via the use of raised flags, when the ball has crossed the goal line or otherwise left the field of play.
Players may not obstruct or foul opponents by kicking or pushing them off the ball. If this happens, the referee will stop play by blowing a whistle, and award a free kick to the fouled team. This will be taken from the spot where the infraction occurred and may be a direct or indirect free kick, depending upon the severity of the foul. A direct free kick means that the player taking the kick can shoot directly at the goal. An indirect free kick means that at least one other player must touch the ball before a shot is taken.
A direct free kick can be deadly if it's awarded within striking range of the goal. When this occurs, defensive players will form a defensive wall between the ball and the goal to assist the keeper in covering the incoming shot. Some players are free kick specialists who relish the opportunity to exploit any weakness in the set up of the wall or simply to use their dead ball skills by bending a shot around the wall or dipping one over it and into the net. (See video linked below.)
If a foul is committed, or a defender puts a hand on the ball while in the penalty area (the 18-yard box around the goal), a penalty kick is awarded. This is also a free kick, but no wall is allowed. The ball is placed upon the penalty spot which is13 yards from the goal and it's a one-on-one situation between the goalkeeper and the designated penalty taker. No other player is allowed in the penalty area until after the ball has been kicked. More often than not, a penalty results in a goal.
Although soccer is a flowing game with no time-outs (except in the case of injury), it also has to be restarted whenever the ball leaves the field of play. If the ball crosses the sideline, it is put back in play by a "throw-in." In a throw-in, the player must have two hands on the ball while holding it behind the head and release the ball in one smooth motion while keeping both feet on the ground. Failure to do this will result in the referee whistling a foul throw and awarding a throw-in to the other team.
If the ball leaves the field by crossing the goal line after last touching a player on the defensive side of the ball, the attacking team is awarded a corner-kick. In a corner-kick, the ball is placed in the corner of the field, at the intersection of the side line and the goal line. This is a dangerous set-play for a defense, and goals resulting from corner kicks are quite common.
If the ball leaves the field after last being touched by a member of the attacking team, the other team is awarded a goal kick. In a goal kick, the ball is placed anywhere in the 6-yard box around the goal where either the goalkeeper or a defender kicks the ball back into play.