Ice hockey stick in the context of "Inline hockey"

Ice hockey or simply known as hockey in North America, is a team sport played on ice skates, usually on an ice skating rink with lines and markings specific to the sport. It belongs to a family of sports called hockey. The two opposing teams score by using their ice hockey sticks to control and advance a vulcanized rubber hockey puck, and then shooting it into the net of the other team, each goal is worth one point. The team with the highest score after an hour of gameplay is declared the winner; ties are broken in overtime or a shootout. In a formal game, each team has six skaters on the ice at a time, barring any penalties, including a goaltender. It is a full contact game and one of the more physically demanding team sports.

The modern sport of ice hockey was developed in Canada, most notably in Montreal, where the first indoor game was played on March 3, 1875. It draws influence from shinty which originated in Scotland, as well as field hockey which originated in England. Some characteristics of ice hockey, such as the length of the ice rink and the use of a puck, have been retained to this day. Amateur ice hockey leagues began in the 1880s, and professional ice hockey originated around 1900. The Stanley Cup, emblematic of ice hockey club supremacy, was initially commissioned in 1892 as the "Dominion Hockey Challenge Cup" and was first awarded in 1893 to recognise the Canadian amateur champion and later became the championship trophy of the National Hockey League (NHL). In the early 1900s, the Canadian rules were adopted by the Ligue Internationale de Hockey sur Glace, in Paris, France, the precursor to the International Ice Hockey Federation (IIHF). The sport was played for the first time at the Olympics during the 1920 Summer Games—today it is a mainstay at the Winter Olympics. In 1994, ice hockey was officially recognized as Canada's national winter sport.

In ice hockey, the goaltender (commonly referred to as goalie or netminder) is the player responsible for preventing the hockey puck from entering their own team's net, thus preventing the opposing team from scoring. The goaltender mostly plays in or near the area in front of the net, called the goal crease (often referred to simply as the crease). Goaltenders tend to stay at or beyond the top of the crease to cut down on the angle of shots. In the modern age of goaltending there are two common styles, butterfly and hybrid (hybrid is a mix of the traditional stand-up style and butterfly technique). Because of the power of shots, the goaltender wears special equipment to protect the body from direct impact.

Goaltenders are one of the most important players on the ice, as their performance may greatly impact the outcome or score of the game. One-on-one situations, such as breakaways and shootouts, have the tendency to showcase a goaltender's pure skill, or lack thereof. No more than one goaltender per team is permitted to be on the ice at any given time. The rules do not oblige the use of a goaltender and so teams may instead opt to play with an extra skater. However the defensive disadvantage that follows means that this strategy is normally used purely as a desperation maneuver when needing to score late in a game. It may also be used when there is a delayed penalty (should the team to be short-handed touch the puck the play will stop as the penalty is called).

Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures.

The term hockey stick graph was popularized by the climatologist Jerry Mahlman, to describe the pattern shown by the Mann, Bradley & Hughes 1999 (MBH99) reconstruction, envisaging a graph that is relatively flat with a downward trend to 1900 as forming an ice hockey stick's "shaft" followed by a sharp, steady increase corresponding to the "blade" portion. The reconstructions have featured in Intergovernmental Panel on Climate Change (IPCC) reports as evidence of global warming. Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science.