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.
At the grassroots level, local club cricket is essentially an amateur pastime for those involved but still usually involves teams playing in competitions at weekends or in the evening. Schools cricket, first known in southern England in the 17th century, has a similar scenario and both are widely played in the countries where cricket is popular. Although there can be variations in game format, compared with professional cricket, the Laws are always observed and club/school matches are therefore formal and competitive events. The sport has numerous informal variants such as French cricket.
If a fielder is injured or becomes ill during a match, a substitute is allowed to field instead of him, but the substitute cannot bowl or act as a captain. The substitute leaves the field when the injured player is fit to return. The Laws of Cricket were updated in 2017 to allow substitutes to act as wicket-keepers, a situation that first occurred when Mumbai Indians' wicket-keeper Ishan Kishan was injured in a match on 18 April 2018.
Previous versions of the Spirit identified actions that were deemed contrary (for example, appealing knowing that the batsman is not out) but all specifics are now covered in the Laws of Cricket, the relevant governing playing regulations and disciplinary codes, or left to the judgement of the umpires, captains, their clubs and governing bodies. The terse expression of the Spirit of Cricket now avoids the diversity of cultural conventions that exist in the detail of sportsmanship – or its absence.
Some species, such as the ground crickets (Nemobiinae), are wingless; others have small fore wings and no hind wings (Copholandrevus), others lack hind wings and have shortened fore wings in females only, while others are macropterous, with the hind wings longer than the fore wings. In Teleogryllus, the proportion of macropterous individuals varies from very low to 100%. Probably, most species with hind wings longer than fore wings engage in flight.
The wicket-keeper and the batsmen wear protective gear because of the hardness of the ball, which can be delivered at speeds of more than 145 kilometres per hour (90 mph) and presents a major health and safety concern. Protective clothing includes pads (designed to protect the knees and shins), batting gloves or wicket-keeper's gloves for the hands, a safety helmet for the head and a box for male players inside the trousers (to protect the crotch area). Some batsmen wear additional padding inside their shirts and trousers such as thigh pads, arm pads, rib protectors and shoulder pads. The only fielders allowed to wear protective gear are those in positions very close to the batsman (i.e., if they are alongside or in front of him), but they cannot wear gloves or external leg guards.
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.
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.
More than 900 species of crickets are described; the Gryllidae are distributed all around the world except at latitudes 55° or higher, with the greatest diversity being in the tropics. They occur in varied habitats from grassland, bushes, and forests to marshes, beaches, and caves. Crickets are mainly nocturnal, and are best known for the loud, persistent, chirping song of males trying to attract females, although some species are mute. The singing species have good hearing, via the tympana on the tibiae of the front legs.
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".
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.