Golf is a club-and-ball sport in which players use various clubs to hit balls into a series of holes on a course in as few strokes as possible.|
Golf is played for the lowest number of strokes by an individual, known as stroke play, or the lowest score on the most individual holes in a complete round by an individual or team, known as match play. Stroke play is the most commonly seen format at all levels, but most especially at the elite level.
A golf course consists of either 9 or 18 holes, each with a teeing ground that is set off by two markers showing the bounds of the legal tee area, fairway, rough and other hazards, and the putting green surrounded by the fringe with the pin (normally a flagstick) and cup.
Playing a hole on a golf course is initiated by putting a ball into play by striking it with a club on the teeing ground (also called the tee box, or simply the tee). For this first shot on each hole, it is allowed but not required for the golfer to place the ball on a tee prior to striking it. A tee is a small peg that can be used to elevate the ball slightly above the ground up to a few centimetres high. Tees are commonly made of wood but may be constructed of any material, including plastic. Traditionally, golfers used mounds of sand to elevate the ball, and containers of sand were provided for the purpose. A few courses still require sand to be used instead of peg tees, to reduce litter and reduce damage to the teeing ground. Tees help reduce the interference of the ground or grass on the movement of the club making the ball easier to hit, and also places the ball in the very centre of the striking face of the club (the "sweet spot") for better distance.
In addition to the officially printed rules, golfers also abide by a set of guidelines called golf etiquette. Etiquette guidelines cover matters such as safety, fairness, pace of play, and a player's obligation to contribute to the care of the course. Though there are no penalties for breach of etiquette rules, players generally follow the rules of golf etiquette in an effort to improve everyone's playing experience.
A maximum of 14 clubs is allowed in a player's bag at one time during a stipulated round. The choice of clubs is at the golfer's discretion, although every club must be constructed in accordance with parameters outlined in the rules. (Clubs that meet these parameters are usually called "conforming".) Violation of these rules can result in disqualification.
The golf swing is outwardly similar to many other motions involving swinging a tool or playing implement, such as an axe or a baseball bat. However, unlike many of these motions, the result of the swing is highly dependent on several sub-motions being properly aligned and timed. These ensure that the club travels up to the ball in line with the desired path; that the clubface is in line with the swing path; and that the ball hits the centre or "sweet spot" of the clubface. The ability to do this consistently, across a complete set of clubs with a wide range of shaft lengths and clubface areas, is a key skill for any golfer, and takes a significant effort to achieve.
A golf stroke uses the muscles of the core (especially erector spinae muscles and latissimus dorsi muscle when turning), hamstring, shoulder, and wrist. Stronger muscles in the wrist can prevent them from being twisted during swings, whilst stronger shoulders increase the turning force. Weak wrists can also transmit the force to elbows and even neck and lead to injury. (When a muscle contracts, it pulls equally from both ends and, to have movement at only one end of the muscle, other muscles must come into play to stabilize the bone to which the other end of the muscle is attached.) Golf is a unilateral exercise that can break body balances, requiring exercises to keep the balance in muscles.
The score achieved for each and every hole of the round or tournament is added to produce the total score, and the player with the lowest score wins in stroke play. Stroke play is the game most commonly played by professional golfers. If there is a tie after the regulation number of holes in a professional tournament, a playoff takes place between all tied players. Playoffs either are sudden death or employ a pre-determined number of holes, anywhere from three to a full 18. In sudden death, a player who scores lower on a hole than all of his opponents wins the match. If at least two players remain tied after such a playoff using a pre-determined number of holes, then play continues in sudden death format, where the first player to win a hole wins the tournament.
The most recent Differentials are logged, up to 20 of them, and then the best of these (the number used depends on the number available) are selected, averaged, multiplied by .96 (an "excellence factor" that reduces the handicap of higher-scoring players, encouraging them to play better and thus lower their handicap), and truncated to the tenths place to produce the "Handicap Index". Additional calculations can be used to place higher significance on a player's recent tournament scores. A player's Handicap Index is then multiplied by the Slope Rating of the course to be played, divided by the average Slope Rating of 113, then rounded to the nearest integer to produce the player's Course Handicap.
The fields for these events include the top several dozen golfers from all over the world. The Masters has been played at Augusta National Golf Club in Augusta, Georgia, since its inception in 1934. It is the only major championship that is played at the same course each year. The U.S. Open and PGA Championship are played at courses around the United States, while the Open Championship is played at courses around the United Kingdom.