Hardcourt

A hardcourt (or hard court) is a surface or floor on which a sport is played, most usually in reference to tennis courts. They are typically made of rigid materials such as asphalt or concrete, and covered with acrylic material to seal the surface and mark the playing lines, while providing some cushioning. Historically, hardwood surfaces were also in use in indoor settings, similar to an indoor basketball court, but these are now rare.

Tennis

Tennis hard courts are made of synthetic/acrylic layers on top of a concrete or asphalt foundation and can vary in color. These courts tend to play medium-fast to fast because there is little energy absorption by the court, like in grass courts. The ball tends to bounce high and players are able to apply many types of spin during play. Flat balls are favored on hard courts because of the extremely quick play style. Speed of rebound after tennis balls bounce on hard courts is determined by how much sand is in the synthetic/acrylic layer placed on top of the asphalt foundation. More sand will result in a slower bounce due to more friction.

Tennis

Tennis is a racket sport that can be played individually against a single opponent (singles) or between two teams of two players each (doubles). Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent's court. The object of the game is to play the ball in such a way that the opponent is not able to play a valid return. The player who is unable to return the ball will not gain a point, while the opposite player will.

Tennis is an Olympic sport and is played at all levels of society and at all ages. The sport can be played by anyone who can hold a racket, including wheelchair users. The modern game of tennis originated in Birmingham, England, in the late 19th century as "lawn tennis". It had close connections both to various field ("lawn") games such as croquet and bowls as well as to the older racket sport of real tennis. During most of the 19th-century in fact, the term "tennis" referred to real tennis, not lawn tennis: for example, in Disraeli's novel Sybil (1845), Lord Eugene De Vere announces that he will "go down to Hampton Court and play tennis."

Tennis (band)

Tennis is an American indie pop band from Denver, Colorado, United States, made up of husband-and-wife duo Alaina Moore and Patrick Riley.

History

The couple met each other while studying philosophy in college, and started the band after they got back from an eight-month sailing expedition down the Eastern Atlantic Seaboard. Their songs document their experiences on the water. They took their name from a joke about Riley playing tennis in college. Prior to forming Tennis, Moore's earliest singing experience was in church choirs during her youth.

Their first releases, both in July 2010, were the "Baltimore" EP on the Underwater Peoples label and the "South Carolina" single on Fire Talk. Tennis released their first studio album, Cape Dory on Fat Possum Records in January 2011. The album, featured on NPR, was based on the couple's experiences during their sailing trip.

During their first tour, James Barone joined the band on drums.

The second Tennis album, Young & Old, was released on Fat Possum Records on February 14, 2012, produced by Patrick Carney of The Black Keys, preceded by the single "Origins", which was issued on Forest Family Records on December 6, 2011.

Tennis (album)

Tennis is the third studio album by Chris Rea, released in 1980.

Track listing

All songs by Chris Rea

Personnel

Hard (surname)

Hard is a surname. Notable people with the surname include:

Complete (complexity)

In computational complexity theory, a computational problem is complete for a complexity class if it is, in a technical sense, among the "hardest" (or "most expressive") problems in the complexity class.

More formally, a problem p is called hard for a complexity class C under a given type of reduction, if there exists a reduction (of the given type) from any problem in C to p. If a problem is both hard for the class and a member of the class, it is complete for that class (for that type of reduction).

A problem that is complete for a class C is said to be C-complete, and the class of all problems complete for C is denoted C-complete. The first complete class to be defined and the most well-known is NP-complete, a class that contains many difficult-to-solve problems that arise in practice. Similarly, a problem hard for a class C is called C-hard, e.g. NP-hard.

Normally it is assumed that the reduction in question does not have higher computational complexity than the class itself. Therefore it may be said that if a C-complete problem has a "computationally easy" solution, then all problems in "C" have an "easy" solution.

Hard (nautical)

A hard is a firm or paved beach or slope by water that is convenient for hauling boats out of the water. The term is especially used in Hampshire, southern England.

See also

References