The ICC also organises competitions that are for several countries at once, including the Cricket World Cup, ICC T20 World Cup and ICC Champions Trophy. A league competition for Test matches played as part of normal tours, the ICC World Test Championship, had been proposed several times, and its first instance began in 2019. A league competition for ODIs, the 2020–22 ICC Cricket World Cup Super League, is planned to begin in 2020. The ICC maintains Test rankings, ODI rankings and T20 rankings systems for the countries which play these forms of cricket.
Cricket has close historical ties with Australian rules football and many players have competed at top levels in both sports. In 1858, prominent Australian cricketer Tom Wills called for the formation of a "foot-ball club" with "a code of laws" to keep cricketers fit during the off-season. The Melbourne Football Club was founded the following year, and Wills and three other members codified the first laws of the game. It is typically played on modified cricket fields.
Crickets are found in many habitats. Members of several subfamilies are found in the upper tree canopy, in bushes, and among grasses and herbs. They also occur on the ground and in caves, and some are subterranean, excavating shallow or deep burrows. Some make home in rotting wood, and certain beach-dwelling species can run and jump over the surface of water.
In 1975, Dr. William H. Cade discovered that the parasitic tachinid fly Ormia ochracea is attracted to the song of the cricket, and uses it to locate the male to deposit her larvae on him. It was the first known example of a natural enemy that locates its host or prey using the mating signal. Since then, many species of crickets have been found to be carrying the same parasitic fly, or related species. In response to this selective pressure, a mutation leaving males unable to chirp was observed amongst a population of Teleogryllus oceanicus on the Hawaiian island of Kauai, enabling these crickets to elude their parasitoid predators. A different mutation with the same effect was also discovered on the neighboring island of Oahu (ca. 100 miles (160 km) away). Recently, new "purring" males of the same species in Hawaii are able to produce a novel auditory sexual signal that can be used to attract females while greatly reducing the likelihood of parasitoid attack from the fly.
The innings (ending with 's' in both singular and plural form) is the term used for each phase of play during a match. Depending on the type of match being played, each team has either one or two innings. Sometimes all eleven members of the batting side take a turn to bat but, for various reasons, an innings can end before they have all done so. The innings terminates if the batting team is "all out", a term defined by the Laws: "at the fall of a wicket or the retirement of a batsman, further balls remain to be bowled but no further batsman is available to come in". In this situation, one of the batsmen has not been dismissed and is termed not out; this is because he has no partners left and there must always be two active batsmen while the innings is in progress.
Limited overs cricket is always scheduled for completion in a single day. There are two types: List A which normally allows fifty overs per team; and Twenty20 in which the teams have twenty overs each. Both of the limited overs forms are played internationally as Limited Overs Internationals (LOI) and Twenty20 Internationals (T20I). List A was introduced in England in the 1963 season as a knockout cup contested by the first-class county clubs. In 1969, a national league competition was established. The concept was gradually introduced to the other leading cricket countries and the first limited overs international was played in 1971. In 1975, the first Cricket World Cup took place in England. Twenty20 is a new variant of limited overs itself with the purpose being to complete the match within about three hours, usually in an evening session. The first Twenty20 World Championship was held in 2007. Limited overs matches cannot be drawn, although a tie is possible and an unfinished match is a "no result".