In some tournaments, line judges who would be calling the serve, were assisted by electronic sensors that beeped to indicate the serve was out. This system was called "Cyclops".[60] Cyclops has since largely been replaced by the Hawk-Eye system.[61][62] In professional tournaments using this system, players are allowed three unsuccessful appeals per set, plus one additional appeal in the tie-break to challenge close line calls by means of an electronic review. The US Open, Miami Masters, US Open Series, and World Team Tennis started using this challenge system in 2006 and the Australian Open and Wimbledon introduced the system in 2007.[63] In clay-court matches, such as at the French Open, a call may be questioned by reference to the mark left by the ball's impact on the court surface.

This discussion is very timely for me because not only is it helping me stabilize my game, my daughter is now six and showing interest in “Playing tennis.” When she was four and five that meant catching and sweeping the ball along the floor with a racket back and forth with me, and now it means gripping the child’ racket her aunt brought her with both hands and hitting FH on the soft coach’s ball I toss or hit softly to her. She is a natural leftie, and I showed her a LH grip with two hands, but often she uses the RH backhand grip instead, and I just let her go with it. What is amazing to me is how good her balance is and how well she steps in and rotates through the stroke, pulling the racket through. She is already an accomplished dancer and seems to understand how her body moves, and that clearly helps, but her synthesis of gripping, which she was taught, swinging, which she imitates, and rotating with balance is just natural.
It is imagined that clock faces were used on court, with a quarter move of the hand to indicate a score of 15, 30, and 45. When the hand moved to 60, the game was over. However, in order to ensure that the game could not be won by a one-point difference in players' scores, the idea of "deuce" was introduced. To make the score stay within the "60" ticks on the clock face, the 45 was changed to 40. Therefore, if both players had 40, the first player to score would receive ten, and that would move the clock to 50. If the player scored a second time before the opponent is able to score, they would be awarded another ten and the clock would move to 60. The 60 signifies the end of the game. However, if a player fails to score twice in a row, then the clock would move back to 40 to establish another "deuce".[4][5]
By 1975, aluminum construction improvements allowed for the introduction of the first American "oversized" racket, which was manufactured by Weed. Prince popularized the oversize racket, which had a head size of approximately 110 square inches (710 cm2). Howard Head was able to obtain a broad patent for Prince, despite the prior art of the Bentley Fortissimo (the first oversize, made in Germany of fiberglass) and the Weed. The patent was rejected by Germany but approved in the USA. The popularity of the Prince aluminum oversize had the side effect of popularizing rackets having other non-standard head sizes such as mid-size 85–90 square inches (550–580 cm2) and mid-plus sizes 95–98 square inches (610–630 cm2). Fairly quickly, midsize frames began to become the most-used frames in the pro tours. Martina Navratilova popularized the midsize graphite racket, with her wins using the Yonex R-7, the first midsize graphite racket made by Yonex. Nearly at the same time, however, she said the "jumbo" rackets (midsize included) should be removed from the sport for making it easier. She said she would use them only because other players could, as they were tournament-legal. Fewer players chose to use oversize rackets, and some switched to midplus frames after their earliest career for more control. Fiberglass frames also had a brief period of limited popularity, making fewer inroads among top players than aluminum. Also, the earliest composites, such as the Head Competition series, used by Arthur Ashe, were made without graphite. These were more flexible than a typical early graphite composite but stiffer than wood, fiberglass, and aluminum.
We’ve now covered scoring, the first step to learn as a tennis beginner — let’s move on to understanding the court. A tennis court is 78 feet long by 27 feet wide, and divided in half length-wise by the net. At each end of the court, there are white baselines — here, the serves are taken. These are also the out-of-bounds lines — a ball must not bounce beyond them or it’s out and the player who hit the ball loses a point.
If time and finances permit, adult beginners should take a beginner tennis clinic and hit lots of balls, period. The clinic should be augmented by private lessons. After the basics are in place, find someone to hit with who can control the ball and see if he or she can practice with you. Take more clinics and hit balls … get exposure to hitting while you work on grip technique and footwork. Set a goal to get into the next level within 6-8 weeks.

Here is a great racquet from a very reputable tennis equipment manufacturer. Wilson is a well-known name when it comes to quality tennis products, to say the least, and this good racquet does not disappoint. It features such things as grippy string technology that quickly dampens the energy of the ball as it strikes the racket so you can get better spin on your return shots. It is also ultra-lightweight and has a new class paint finish that gives it some style.

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The industry has changed so much, and manufacturers are finding ways to keep you on the court. Wilson’s Countervail technology helps reduce muscle fatigue to keep you on the court. Head’s Graphene 360 offers a solid, dampened response at contact for more comfort. Babolat’s Cortex Pure Feel features a new material throughout the hoop for better shock absorption. The list goes on.
A serve (or, more formally, a "service") in tennis is a shot to start a point. The serve is initiated by tossing the ball into the air and hitting it (usually near the apex of its trajectory) into the diagonally opposite service box without touching the net. The serve may be hit under- or overhand although underhand serving remains a rarity.[73] If the ball hits the net on the first serve and bounces over into the correct diagonal box then it is called a "let" and the server gets two more additional serves to get it in. There can also be a let if the server serves the ball and the receiver isn't prepared.[74] If the server misses his or her first serve and gets a let on the second serve, then they get one more try to get the serve in the box.
Kolkmann says that asphalt courts can also develop low areas over time due to settling of the soil or base under the asphalt surface. "With a post-tensioned slab, this area can be bridged and no settling will occur. In addition, concrete courts can often be installed on unstable soils where it would be cost-prohibitive to do extensive excavating and base work to support an asphalt court," he says.
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.[1] It had close connections both to various field (lawn) games such as croquet and bowls as well as to the older racket sport today called real tennis. During most of the 19th century, in fact, the term tennis referred to real tennis, not lawn tennis.