Ice hockey is played by two teams of six skaters: one goalie and five outfield players. The game is fast, physical, and played in three zones, and the players rotate in groups called lines. This guide explains the positions, the zones, and why coaches change lines so often.

The three zones

The rink is divided into three zones by two blue lines. Each team defends one end zone and attacks the other; the middle section is the neutral zone. The basic attacking problem is getting the puck from your own end, through the neutral zone, into the other team's end — without going offside, which happens when an attacking player crosses the blue line into the attacking zone before the puck does.

Players also need to know the goal lines, the red centre line, and the faceoff circles, but the blue lines are the ones that shape play: they decide offside, and they mark where the attacking zone begins.

The goalie: the last line

The goalie is the only player whose job is entirely defensive. Goalies wear extra padding and a wider stick, guard a goal that is six feet wide, and are allowed to hold the puck and stop play in ways other players cannot. A goalie who covers the puck with their glove causes a faceoff, which resets play in their team's favour.

Modern goalies mostly play a style called butterfly: they drop to their knees to cover the bottom of the net and use their leg pads to block low shots, while their glove and blocker handle shots to the upper corners. The position is mentally brutal, because a goalie can play brilliantly for fifty minutes and be remembered for one mistake.

Defencemen: two players, two jobs

Each team plays two defencemen, and they have distinct roles:

• Stay-at-home defenceman: the more defensive of the pair. Their priorities are clearing the puck from their own end, blocking shots, and physically separating opponents from the puck. They rarely lead rushes up the ice.
• Offensive defenceman: joins the attack, moves the puck out of the defensive zone with passes or skating, and takes shots from the blue line. The trade-off is risk: when an offensive defenceman pushes forward, their partner must cover behind them.

Defencemen usually play in pairs that stay together for long stretches, because knowing your partner's habits matters more on defence than anywhere else on the ice.

Forwards: centre and wingers

The three forwards are a centre and two wingers, left and right. Their roles differ:

• Centre: the playmaker and the faceoff specialist. Centres take the faceoffs, support both the attack and the defence, and cover the middle of the ice. In their own end, the centre usually drops low to help the defencemen.
• Wingers: play along the boards on their side of the ice. Their jobs are winning puck battles on the boards, driving to the net, and screening the goalie so shots are harder to stop. The left winger and right winger mirror each other, but coaches often put a stronger shooter on one side and a stronger checker on the other.

Forwards are also the first line of defence. When the other team has the puck, forwards backcheck — skating hard back into their own end to pressure the puck carrier — and the quality of a team's backchecking often decides close games.

Lines: why players change every minute

Forwards play in lines of three (a centre plus two wingers), and most teams roll four lines through a game. Defencemen play in three pairs. Shifts are short, usually under a minute, because skating at full effort is exhausting. Coaches change lines on the fly, with players hopping over the boards while play continues, or during stoppages when the whole line can change at once.

Line changes are tactical. A coach matches a defensive line against the other team's best scorers, sends an attacking line out after an icing call, or shortens the bench late in a close game by playing only the top two lines. Watching which line is on the ice, and against whom, tells you what a coach is thinking.

Special teams: power plays and penalty kills

When a player is penalised, their team plays short-handed, usually with four skaters against five, for two or five minutes depending on the penalty. The team with the extra skater is on the power play, and the short-handed team is on the penalty kill. Special-teams units are separate from normal lines: power-play units load up on scorers and a quarterback defenceman on the blue line, while penalty-kill units use defensive forwards and shot-blocking defencemen. A team that wins the special-teams battle usually wins the game.

Questions, answered

How many players are on the ice? Six per team: one goalie, two defencemen, and three forwards (a centre and two wingers).

What is a line? A group of three forwards who play together, changed as a unit. Teams usually roll four lines.

Why are shifts so short? Skating at full effort is exhausting, so players change every minute or so to stay fresh.

What is offside? An attacking player crossing the blue line into the attacking zone before the puck does.

What is icing? Shooting the puck from behind the centre line all the way past the other team's goal line without it being touched. The offending team cannot change lines before the faceoff.

What to watch next

Watch one player for a whole shift instead of following the puck: a centre's route through all three zones tells you more about the game than any highlight. Head to the live scores section to see which ice hockey matches are on today, and check the ice hockey page for fixtures and results.