The National Lacrosse League is North America's premier professional indoor lacrosse league. The NLL has nine teams playing in the major markets of the United States and Canada. NLL teams each play an 18-game regular season schedule (nine home and nine away) that begins in December and runs through May, followed by the Champion's Cup Playoffs. All games are played on the weekends. Professional indoor lacrosse combines the physical play of hockey with the high scoring, fast pace and play-making style of basketball. Indoor lacrosse is played inside the confines of an ice hockey rink, with glass and rink boards intact. The playing surface consists of a green dieter turf carpet that is laid down over the hockey ice. The two teams combine to score a total of 23 goals on average during an NLL game.