The main objective of each team is to score more runs than their opponents but, in some forms of cricket, it is also necessary to dismiss all of the opposition batsmen in their final innings in order to win the match, which would otherwise be drawn. If the team batting last is all out having scored fewer runs than their opponents, they are said to have "lost by n runs" (where n is the difference between the aggregate number of runs scored by the teams). If the team that bats last scores enough runs to win, it is said to have "won by n wickets", where n is the number of wickets left to fall. For example, a team that passes its opponents' total having lost six wickets (i.e., six of their batsmen have been dismissed) have won the match "by four wickets".
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.
Before a match begins, the team captains (who are also players) toss a coin to decide which team will bat first and so take the first innings. Innings is the term used for each phase of play in the match. In each innings, one team bats, attempting to score runs, while the other team bowls and fields the ball, attempting to restrict the scoring and dismiss the batsmen. When the first innings ends, the teams change roles; there can be two to four innings depending upon the type of match. A match with four scheduled innings is played over three to five days; a match with two scheduled innings is usually completed in a single day. During an innings, all eleven members of the fielding team take the field, but usually only two members of the batting team are on the field at any given time. The exception to this is if a batsman has any type of illness or injury restricting his or her ability to run, in this case the batsman is allowed "A Runner" who can run between the wickets when the batsman hits a scoring run or runs. The order of batsmen is usually announced just before the match, but it can be varied.
Crickets have a cosmopolitan distribution, being found in all parts of the world with the exception of cold regions at latitudes higher than about 55° North and South. They have colonised many large and small islands, sometimes flying over the sea to reach these locations, or perhaps conveyed on floating timber or by human activity. The greatest diversity occurs in tropical locations, such as in Malaysia, where 88 species were heard chirping from a single location near Kuala Lumpur. A greater number than this could have been present because some species are mute.
Crickets feature as major characters in novels and children's books. Charles Dickens's 1845 novella The Cricket on the Hearth, divided into sections called "Chirps", tells the story of a cricket which chirps on the hearth and acts as a guardian angel to a family. Carlo Collodi's 1883 children's book "Le avventure di Pinocchio" (The Adventures of Pinocchio) featured "Il Grillo Parlante" (The Talking Cricket) as one of its characters. George Selden's 1960 children's book The Cricket in Times Square tells the story of Chester the cricket from Connecticut who joins a family and their other animals, and is taken to see Times Square in New York. The story, which won the Newbery Honor, came to Selden on hearing a real cricket chirp in Times Square.
Females are generally attracted to males by their calls, though in nonstridulatory species, some other mechanism must be involved. After the pair has made antennal contact, a courtship period may occur during which the character of the call changes. The female mounts the male and a single spermatophore is transferred to the external genitalia of the female. Sperm flows from this into the female's oviduct over a period of a few minutes or up to an hour, depending on species. After copulation, the female may remove or eat the spermatophore; males may attempt to prevent this with various ritualised behaviours. The female may mate on several occasions with different males.
Cricket is a multi-faceted sport with multiple formats that can effectively be divided into first-class cricket, limited overs cricket and, historically, single wicket cricket. The highest standard is Test cricket (always written with a capital "T") which is in effect the international version of first-class cricket and is restricted to teams representing the twelve countries that are full members of the ICC (see above). Although the term "Test match" was not coined until much later, Test cricket is deemed to have begun with two matches between Australia and England in the 1876–77 Australian season; since 1882, most Test series between England and Australia have been played for a trophy known as The Ashes. The term "first-class", in general usage, is applied to top-level domestic cricket. Test matches are played over five days and first-class over three to four days; in all of these matches, the teams are allotted two innings each and the draw is a valid result.