Hockey is played on a rink 200' long and 85' wide, with rounded corners. The ice surface has painted lines on it, which indicate face-off circles, the goal crease, and the various zones. The most important lines are the red line (which runs across the center of the ice) and the blue lines (which are parallel to the red line and are painted 73' from each end of the rink). The red line indicates center ice, and regulates how far players can pass and shoot. The blue lines divide up the ice into three zones. Each team plays from one side of the ice, and the area behind a team's blue line is called its defending zone. The area behind the opposing team's blue line is called the attacking zone. Finally, the area between the two blue lines is called the neutral zone.
Thirteen feet from each end of the ice, right in the center, is a stationary set of goal posts with a net attached behind them. The object of the game is to put the puck in the net more times than the other team does. The posts are six feet apart and the top post (or crossbar) is four feet from the ice. A red line called the goal line is painted between the two posts, and the puck must cross this line entirely for a goal to be counted. We know it's confusing that the place where the pucks go and the act of putting a puck there are both called the same thing (a goal). You have two choices: you can either get used to it or you can always call the goal "the net." A blue area is painted in front of the goal. It goes out a foot from each side, then extends straight forward for four and a half feet and ends in a semi-circle whose furthest point is six feet from the goal line. This is called the crease.
There are three basic kinds of players: forwards, defensemen, and goaltenders (goalies). Unless a team is shorthanded due to a penalty or overtime, each team will have six players on the ice during play. Three forwards line up at the front of the team, and they are (from left to right) the left wing, the center, and the right wing. Two defensemen line up behind them, one on the left and one on the right. The goalie is the sixth player. The forwards are responsible for most of the offense, and they tend to stay out front, while the defensemen are largely responsible for hanging back and making sure they are ready to protect the defensive zone. The goalie rarely strays far from his crease, but he does skate out and pass pucks to the other players.
One of the interesting things about hockey is that all the players have to be aware of and involved in what is going on all over the rink. Every movement of the puck and the opposing team's players demands a reaction from each player on the team. Forwards must be responsible for defending their own zone, and defensemen must play a role in the offense.
Forwards tend to stick to one position for most of their careers, but they move around a bit from time to time as the team needs them to or if the coach thinks, for example, that a left wing might be better suited to playing at center. Defensemen are more flexible, in that they can usually play either side, and some will occasionally fill in at a forward position. Goalies are very specialized players. They have to stand in front of the net and stop pucks, some of which are travelling at 90 miles per hour or more. They never play other positions, and other players never play in goal (with a few rare exceptions).
Each player carries a stick and the players use these sticks to pass and shoot a puck, a small, hard rubber disk, around the rink. They also use these sticks to hit each other and to smash on the boards in disgust, but they're not supposed to do that. In order to avoid being hurt by the sticks and the pucks, the players wear a good deal of padding and they are required by league rules to wear helmets. This is a relatively new rule in the NHL, and many players were resistant to the wearing of helmets when it was first instituted. There is still a certain amount of macho resistance to wearing face shields, probably because it is bad form to fight when wearing a face shield and, therefor, wearing one proclaims a player to be something of a sissy. The players also wear skates, of course. For skating. On the ice.
Regulation time and overtime
Each game consists of three periods of twenty minutes each. The players get about fifteen minutes of rest between periods. In the regular season, if the game is tied at the end of regulation time (the end of the third period), the teams almost immediately go into overtime, which is an extra five minutes of playing time. During these five-minute overtimes there are only five players on the ice. You will often hear this format referred to as 4-on-4 because although there are five players on the ice for each team only four of them are skating against each other. This is to allow more room to skate and to allow teams to capitalize on their fastest and most skilled players in an attempt to resolve the contest. The overtime in hockey is "sudden death" because if either team scores at any time, that team automatically wins and the overtime period ends. If neither team scores by the end of overtime, the game is declared a tie.
During the playoffs, if the game is tied at the end of regulation time the game will go into overtime, but the players get a fifteen minute rest, and the overtime period is also twenty minutes. These overtime periods are played with six players (or 5-on-5) and are identical to periods in regulation time except that they are "sudden death." The game will continue until one team scores and wins, so overtime playoff games can go into double overtime, triple overtime, etc. There are no ties in the playoffs.
In each game there are one or two referees, who make on-ice decisions regarding penalties, goals, and other matters. They wear striped jerseys with orange bands on the arms and they skate around, get in the way of players, and fail to see obvious infractions committed against your team's players. There are also two linesmen, who wear striped jerseys with no orange bands, skate around, get in the way of players, keep track of offsides, passing, and icing and offer opinions to the referee if he asks. Other officials include the time keeper, the official scorer, two goal judges (one behind each net), and the video goal judge. The latter official conducts video reviews of certain plays to see if questionable goals count or not.
(reproduced from soyouwanna.com)