International cricket
In addition to the one-day series and tournaments organised by the nations themselves, the ICC organises two One Day International tournaments. The World Cup is held every four years; it involves all the Test-playing nations and a number of teams advancing from the immediately preceding ICC World Cup Qualifier. The ICC Champions Trophy, previously known as the ICC Knockout Cup, is a shorter tournament held every four years in between World Cups. The ICC also organises a T20 International tournament, the ICC World Twenty20, which is generally held every two years and, as in the latest competition, involves the ten full ICC members and six associate members who qualified through a qualifier competition, the ICC World Twenty20 Qualifier.
Test cricket
Test cricket is the longest form of the sport of cricket and is considered its highest standard. Test matches are played between national representative teams with "Test status", as determined and conferred by the International Cricket Council (ICC). The two teams of 11 players each play a four-innings match, which may last up to five days (or longer in some historical cases). It is generally considered the most complete examination of teams' playing ability and endurance. The name "Test" stems from the long, gruelling match being both mentally and physically testing.