Ice hockey is a team sport played on ice in which skaters use sticks to shoot a hard rubber hockey puck into their opponent's net to score points. In some countries, such as Canada and the United States, it is known as "hockey"; the name "ice hockey" is used in countries where "hockey" generally refers to field hockey.
A team usually consists of four lines of three forwards, three pairs of defensemen, and two goalies. Five members of each team skate up and down the ice trying to take the puck and score a goal against the opposing team. Each team has a goaltender who tries to stop the puck from going into the goal.
162 of 177 medals at the IIHF World Championships have been taken by seven nations: Canada, the Czech Republic, Finland, Russia, Slovakia, Sweden and the United States. Of the 66 medals awarded in men's competition at the Olympics from 1920, only six medals did not go to one of those countries. All 12 Olympic and 36 IIHF World Women's Championships medals have gone to one of these seven countries, and every gold medal in both competitions has been won by either Canada or the United States.