Test cricket is a format of cricket with the longest match duration and is considered the game's highest standard. Test matches are played between national representative teams that have been granted Test status, as determined and conferred by the International Cricket Council (ICC). They are called Tests because the long, gruelling nature of matches makes them mentally and physically testing. Two teams of 11 players each play a four-innings match, which may last up to five days. It is generally considered the most complete examination of a team's endurance and ability.