A tennis tour (or tennis circuit) is tennis played in tournament format at a series of venues – a – over during a set period of weeks or months. Professional tour tennis is played globally with one season consisting of one calendar year. Several tournaments are held each week as players win prize money and earn ranking points. A player's ranking determines her or his ability to enter a particular tournament, as tournaments vary in the amount money and points obtainable. Winning a tournament typically requires winning four to six matches in succession, generally a match a day, as play is single-loss elimination.