how many teams does it have?
31 teams - 24 in the United States and 7 in Canada.
National Hockey League
currently comprising 31 teams: 24 in the United States and 7 in Canada. 
who is wayne gretzky? A Canadian former professional ice hockey player and former head coach. can you name a few teams he has played for that game? The Edmonton Oilers,  St. Louis Blues which teams did he coach? UNANSWERABLE can you tell me any of his breakthroughs during his playing career? Gretzky was the top scorer in the 1978 World Junior Ice Hockey Championships you had mentioned two teams he has played for, which league are those teams a part of? National Hockey League (NHL) when was the above organization formed? The National Hockey League was established in 1917
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National Hockey League [SEP] Introduction
The National Hockey League (NHL; ) is a professional ice hockey league in North America, currently comprising 31 teams: 24 in the United States and 7 in Canada. The NHL is considered to be the premier professional ice hockey league in the world, and one of the major professional sports leagues in the United States and Canada. The Stanley Cup, the oldest professional sports trophy in North America, is awarded annually to the league playoff champion at the end of each season. The National Hockey League was organized on November 26, 1917, at the Windsor Hotel in Montreal after the suspension of operations of its predecessor organization, the National Hockey Association (NHA), which had been founded in 1909 in Renfrew, Ontario.