A tennis court is the venue where the sport of tennis is played. It is a firm rectangular surface with a low net stretched across the centre. The same surface can be used to play both doubles and singles matches. A variety of surfaces can be used to create a tennis court, each with its own characteristics which affect the playing style of the game.
The dimensions of a tennis court are defined and regulated by the International Tennis Federation (ITF) governing body and are written down in the annual 'Rules of Tennis' document.  The court is 78 ft (23.77 m) long. Its width is 27 ft (8.23 m) for singles matches and 36 ft (10.97 m) for doubles matches.  The service line is 21 ft (6.40 m) from the net.  Additional clear space around the court is needed in order for players to reach overrun balls for a total of 60 ft (18 m) wide and 120 ft (37 m) long. A net is stretched across the full width of the court, parallel with the baselines, dividing it into two equal ends. The net is 3 ft 6 in (1.07 m) high at the posts, and 3 ft (0.914 m) high in the center.  The net posts are 3 ft (0.914 m) outside the doubles court on each side or, for a singles net, 3 ft (0.914 m) outside the singles court on each side.
Based on the standard rules of tennis, the size of the court is measured to the outside of the respective baselines and sidelines. The "service" lines ("T" and the "service" line) are centered. The ball must completely miss the line to be considered "out". This also means that the width of the line (except for the center service line) is irrelevant to play. The center service line is 2 in (5 cm), the other lines are between 1 in (2.5 cm) and 2 in (5 cm) wide, whereas the baseline may be up to 4 in (10 cm) wide. 
The ITF's Play and Stay campaign promotes playing on smaller courts with slower red, orange, and green balls for younger children. This gives children more time and control so they can serve, rally, and score from the first lesson on courts that are sized to fit their bodies. The ITF has mandated that official competition for children aged 10 years and under should be played on "Orange" courts 18 m (59 ft) long by 6.4 m (21 ft) wide. Competition for children under 8 years is played on "Red" courts that are 11 m (36 ft) long and 5.5 m (18 ft) wide. The net is always 0.8 m high in the center. 
Tennis is played on a variety of surfaces and each surface has its own characteristics which affect the playing style of the game. There are four main types of courts depending on the materials used for the court surface: clay courts, hard courts, grass courts and carpet courts. The International Tennis Federation (ITF) lists different surfaces and properties and classifies surfaces into one of five pace settings: 
Of the current four Grand Slam tournaments, the Australian and US Open use hard courts, the French Open is played on clay, and Wimbledon, the only Grand Slam to have always been played on the same surface, is played on grass. The Australian Open switched from grass to hard courts in 1988 and in its early years the French championship alternated between clay and sand/rubble courts. The US Open is the only major to have been played on three surfaces; it was played on grass from its inception until 1974, clay from 1975 until 1977 and hard courts since it moved from the West Side Tennis Club to the National Tennis Center in 1978.
ITF uses the following classification for tennis court surface types: 
|A||Acrylic||Textured, pigmented, resin-bound coating|
|B||Artificial clay||Synthetic surface with the appearance of clay|
|C||Artificial grass||Synthetic surface with the appearance of natural grass|
|E||Carpet||Textile or polymeric material supplied in rolls or sheets of finished product|
|F||Clay||Unbound mineral aggregate|
|H||Grass||Natural grass grown from seed|
|J||Other||E.g. modular systems (tiles), wood, canvas|
Clay courts are made of crushed shale, stone or brick.  The French Open is the only Grand Slam tournament to use clay courts.
Clay courts slow down the ball and produces a high bounce in comparison to grass or hard courts.  For this reason, the clay court takes away many of the advantages of big serves, which makes it hard for serve-based players to dominate on the surface. Clay courts are cheaper to construct than other types of tennis courts, but a clay surface costs more to maintain. Clay courts need to be rolled to preserve flatness. The clay's water content must be balanced; green clay courts generally require the courts to be sloped to allow water run-off.
Clay courts are more common in Europe and Latin America than in North America, and tend to heavily favour baseline players.
Historically for the Grand Slams clay courts have been used at the French Open since 1891 and the US Open from 1975 to 1977.
Grass courts are the fastest type of courts in common use.  They consist of grass grown on very hard-packed soil, which adds additional variables: bounces depend on how healthy the grass is, how recently it has been mowed, and the wear and tear of recent play. Points are usually very quick where fast, low bounces keep rallies short, and the serve plays a more important role than on other surfaces. Grass courts tend to favour serve-and-volley tennis players.
Grass courts were once among the most common tennis surfaces, but are now rare due to high maintenance costs, as they must be watered and mown often, and take a longer time to dry after rain than hard courts.
Historically for the Grand Slams grass courts have been used at Wimbledon since 1877, the US Open from 1881 to 1974, and the Australian Open from 1905 to 1987.
Hard courts are made of uniform rigid material, often covered with an acrylic surface layer  to offer greater consistency of bounce than other outdoor surfaces.  Hard courts can vary in speed, though they are faster than clay but not as fast as grass courts. The quantity of sand added to the paint can greatly affect the rate at which the ball slows down. 
The US Open is played on Laykold while the Australian Open is played on GreenSet, both acrylic-topped hard court surfaces.
Historically for the Grand Slams hard courts have been used at the US Open since 1978 and the Australian Open since 1988.
"Carpet" in tennis means any removable court covering.  Indoor arenas store rolls of rubber-backed court surfacing and install it temporarily for tennis events, but they are not in use any more for professional events. A short piled form of artificial turf infilled with sand is used for some outdoor courts, particularly in Asia. Carpet is generally a fast surface, faster than hardcourt, with low bounce. 
Notable tennis tournaments previously held on carpet courts were the WCT Finals, Paris Masters, U.S. Pro Indoor and Kremlin Cup. Since 2009, their use has been discontinued on the top tier of the ATP. ATP Challenger Tour tournaments such as the Trofeo Città di Brescia still use carpet courts. The WTA Tour's last carpet court event, the International-level Tournoi de Québec, was discontinued after 2018.
Some tennis courts are indoors, which allows play regardless of weather conditions and is more comfortable for spectators.
Different court surfaces have been used indoors. Hard courts are most common indoors, as they are the easiest to install and maintain. If the installation is permanent, they are constructed on an asphalt or concrete base, as with outdoor courts. Temporary indoor hard courts are typically constructed using wooden floor panels topped with acrylic which are installed over the venue's standard floor. This is the system used for modern indoor professional events such as the ATP Finals.
Clay courts can be installed indoors with subsurface watering systems to keep the clay from drying out, and have been used for Davis Cup matches.
Carpet courts were once the most prominent of indoor surfaces, especially in temporary venues, but have largely been replaced by removable hard courts. They were used on both the ATP World Tour and World Championship Tennis circuits, though no events currently use them.
Historically, other surfaces have been used indoors such as wood courts at the defunct World Covered Court Championships and London Indoor Professional Championships.
The conclusion of the Wimbledon Championships, in 2012, was played on the lawn of Centre Court under the closed roof and artificial lights; the Halle Open has also seen a number of matches played on its grass court in the Gerry Weber Stadion with the roof closed. These, however, are outdoor venues with retractable roofs.
Common tennis court terms:
Tennis is a racket sport that is played either 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 manoeuvre 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 validly will not gain a point, while the opposite player will.
The Grand Slam in tennis is the achievement of winning all four major championships in one discipline in a calendar year, also referred to as the "Calendar-year Grand Slam" or "Calendar Slam". In doubles, a team may accomplish the Grand Slam playing together or a player may achieve it with different partners. Winning all four major championships consecutively but not within the same calendar year is referred to as a "non-calendar-year Grand Slam", while winning the four majors at any point during the course of a career is known as a "Career Grand Slam".
The ATP Finals is the season-ending championship of the ATP Tour. It is the most significant event in the annual ATP calendar after the four majors as it features the top-eight singles players and top-eight doubles teams based on their results throughout the season. The eighth spot is reserved, if needed, for a player or team who won a major in the current year and are ranked from 8th–20th. The tournament is sometimes referred to as a "fifth Grand Slam," due to the prestige that comes with qualifying for and winning the event.
A hardcourt is a surface or floor on which a sport is played, most usually in reference to tennis courts. It is typically made of rigid materials such as asphalt or concrete, and covered with acrylic resins 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 surfaces are rare now.
A grass court is one of the four different types of tennis court on which the sport of tennis, originally known as "lawn tennis", is played. Grass courts are made of grasses in different compositions depending on the tournament.
A point in tennis is the smallest subdivision of the match. A point can consist of a double fault by the server, in which case the point is automatically won by the receiver. In all other cases, a point begins when a legal serve is hit by the server to the receiver on the opposite side of the court, and continues until one side fails to legally return the ball to the opposite side. Whichever side fails to do so loses the point and their opponent wins it.
This page is a glossary of tennis terminology.
Players use different strategies while playing tennis to enhance their own strengths and exploit their opponent's weaknesses in order to gain the advantage and win more points.
A clay court is one of the types of tennis court on which the sport of tennis, originally known as "lawn tennis", is played. Clay courts are made of crushed stone, brick, shale, or other unbound mineral aggregate depending on the tournament.
Traditionally, tennis is played between two people in a singles match, or two pairs in a doubles match. Tennis can also be played on different courts, including grass courts, clay courts, hard courts, and artificial grass courts.
The 1975 US Open was a tennis tournament that took place on the outdoor clay courts at the West Side Tennis Club in Forest Hills, Queens, in New York City, United States. The tournament ran from 27 August until 7 September. It was the 95th staging of the US Open, and the fourth Grand Slam tennis event of 1975. During the final three years at the Forest Hills location, 1975-1977, the US Open was played on a green-colored Har-Tru clay surface, a surface slightly harder and faster than red clay. The switch came after player complaints about the poor state and uneven ball bounce on the grass courts in Forest Hills. The tie-break scoring system changed in this championship. Previously a sudden death point was played at 4–4 with the winner the first to 5 points. It changed to the 13 point tie-break first to 7 points or the first player to win by two clear points if the scores reached 6–6.
The tennis rivalry between Roger Federer and Rafael Nadal is considered the greatest in the history of the sport. Federer and Nadal played each other 40 times, with Nadal leading 24–16 overall, including 14–10 in finals.
The Evert–Navratilova rivalry was a tennis rivalry in the 1970s and 1980s between Chris Evert and Martina Navratilova, widely regarded as two of the greatest tennis players of all time. It is considered to be one of the greatest rivalries in tennis history and sports in general. The pair contested 80 matches between 1973 and 1988, with Navratilova leading the overall head-to-head 43–37 and 36–24 in finals.
The following outline is provided as an overview of and topical guide to tennis. Tennis is a sport usually played between two players (singles) or between two teams of two players each (doubles). Each player uses a specialized racquet that is strung to strike a hollow rubber ball covered with felt over a net into the opponent's court.
The Laver–Rosewall rivalry was a tennis rivalry in the 1960s and 1970s between Rod Laver and Ken Rosewall, widely regarded as two of the greatest tennis players of all time. In 1956 both players toured in the amateur circuit but never faced each other. Rosewall turned professional in January 1957 and the two did not meet until January 1963 when Laver turned pro. They played many times until 1977 when both semi-retired from the main tour.
A serve in tennis is a shot to start a point. A player will hit the ball with a racquet so it will fall into the diagonally opposite service box without being stopped by the net. Normally players begin a serve by tossing the ball into the air and hitting it. The ball can only touch the net on a return and will be considered good if it falls on the opposite side. If the ball contacts the net on the serve but then proceeds to the proper service box, it is called a let; this is not a legal serve in the major tours although it is also not a fault. Players normally serve overhead; however serving underhand is allowed. The serve is the only shot a player can take their time to set up instead of having to react to an opponent's shot; however, as of 2012, there is a 25-second limit to be allowed between points.
This article covers the period from 1877 to present. Before the beginning of the Open Era in April 1968, only amateurs were allowed to compete in established tennis tournaments, including the four Grand Slam tournaments. Wimbledon, the oldest of the majors, was founded in 1877, followed by the US Open in 1881, the French Open in 1891 and the Australian Open in 1905. Beginning in 1905 and continuing to the present day, all four majors have been played yearly, with the exception of during the two World Wars, 1986 for the Australian Open, and 2020 for Wimbledon. The Australian Open is the first major of the year (January), followed by the French Open (May–June), Wimbledon (June–July) and the US Open (August–September). There was no prize money and players were compensated for travel expenses only. A player who wins all four majors, in singles or as part of a doubles team, in the same calendar year is said to have achieved a "Grand Slam". If the player wins all four consecutively, but not in the same calendar year, it is called a "Non-Calendar Year Grand Slam". Winning all four at some point in a career, even if not consecutively, is referred to as a "Career Grand Slam". Winning the four majors and a gold medal in tennis at the Summer Olympics in the same calendar year has been called a "Golden Slam" since 1988. Winning all four majors plus an Olympic gold at some point in a career, even if not consecutively, is referred to as a "Career Golden Slam". Winning the year-end championship while also having won a Golden Slam is referred to as a "Super Slam". Winning all four majors, an Olympic gold, and the year-end championships at some point in a career, even if not consecutively, is referred to as a "Career Super Slam". Winning the four majors in all three disciplines a player is eligible for–singles, doubles and mixed doubles–is considered winning a "boxed set" of Grand Slam titles.
A carpet court is a type of tennis court. The International Tennis Federation describes the surface as a "textile or polymeric material supplied in rolls or sheets of finished product." It is one of the fastest court types, second only to grass courts. The use of carpet courts in ATP Tour competitions ended in 2009. In women's tennis, no WTA Tour tournaments have used carpet courts since the last edition of the Tournoi de Québec in 2018. ATP Challenger and ITF circuit level tournaments with carpet courts continue to exist up to the present (2022).
This was a tennis rivalry played between French player Jean Borotra and the French player Henri Cochet, which in their respective careers the met 16 times from 1922 until 1949.