Tenpin bowling is a type of bowling in which a bowler rolls a bowling ball down a wood or synthetic lane toward ten pins positioned evenly in four rows in an equilateral triangle. The goal is to knock down all ten pins on the first delivery (a strike), or failing that, on the second delivery (a spare). While many people approach modern tenpin bowling simply as a recreational pastime, competitive bowlers consider it a demanding sport requiring precision and skill.
The , lane is bordered along its length by gutters (channels) that collect errant balls. The lane's long and narrow shape limits straight-line ball paths to angles that are shallower than the ideal entry angle(s) for achieving strikes. Accordingly, bowlers impart side rotation to hook (curve) the ball into the pins to increase the likelihood of striking. A long approach area is used by the bowler to impart speed and apply side rotation to the bowling ball, and is separated from the lane by a foul line. Crossing this foul line is detectable via sensors and results in a score of zero for the delivery in league or tournament play.
Oil is applied to approximately the first two-thirds of the lane's length to allow a "skid" area for the ball before it encounters friction and hooks. The oil is applied in different lengths and layout patterns, especially in professional and tournament play, to add complexity and regulate challenge in the sport. When coupled with technological developments in bowling ball designs dating back to the early 1990s, easier oil patterns commonly used for league play have enabled many league bowlers to achieve scores rivaling those of professional bowlers who compete on more difficult patterns—a development that has caused substantial controversy.
Tenpin bowling arose in the early 1800s as an alternative to nine-pin bowling, with truly standardized regulations not being agreed on until nearly the end of that century. After the development of automated mechanical pinsetters, the sport enjoyed a "golden age" in the mid twentieth century. Following substantial declines since the 1980s in both professional tournament television ratings and amateur league participation, bowling centers have increasingly expanded to become diverse entertainment centers. In the 2020s, pinsetter cost and maintenance motivated some bowling centers to adopt string pinsetters.
When people use the bare term, bowling, they usually mean tenpin bowling. Tenpin, or less commonly, big-ball, are prepended in the English-speaking world to distinguish it from other bowling types such as bowls, candlepin, duckpin and five-pin.
Facilities and equipment Lanes
Tenpin bowling lanes are from the foul line to the center of the head pin (1-pin), with guide arrows (aiming targets) about from the foul line. The lane is wide and has 39 wooden boards, or is made of a synthetic material with the 39 "boards" simulated using marking lines. The approach has two sets of dots, respectively and behind the foul line, to help with foot placement.
Modern bowling lanes have oil patterns designed not only to shield the lanes from damage from bowling ball impacts, but to provide bowlers with different levels of challenge in achieving strikes. As illustrated, a typical house pattern (or THS, typical house shot) has drier outside portions that give bowling balls more friction to hook (curve) into the pocket, but heavier oil concentrations surrounding the centerline so that balls slide directly toward the pocket with less hooking. In the more challenging sport patterns used in tournaments and professional-level matches, a "flat" oil pattern—one with oil distributed more evenly from side to side—provides little assistance in guiding the ball toward the pocket, and is less forgiving with regard to off-target shots. The ratio of centerline oil concentration to side oil concentration (the oil ratio) can exceed 10-to-1 for THSs but is restricted to 3-to-1 or less for sport shots.
Lane oils, also called lane conditioners, are composed of about 98% mineral oil that, with numerous additives, are designed to minimize breakdown and carry-down that would change ball reaction after repeated ball rolls. Lane oils are characterized by different levels of viscosity, with oils of higher viscosity (thicker consistency) being more durable but causing balls to slow and hook earlier than lower-viscosity oils.
Balls
Rubber balls (introduced in 1905) were eventually supplanted by polyester ("plastic") balls (1959) and polyurethane ("urethane") balls (1980s). Coverstocks (surfaces) of bowling balls then evolved to increase the hook-enhancing friction between ball and lane: reactive resin balls arrived in the early 1990s, and particle-enhanced resin balls in the late 1990s. Meanwhile, the increasingly sophisticated technology of internal cores (also called weight blocks) has increased balls' dynamic imbalance, which, in conjunction with the coverstocks' increased friction, enhances hook (curving) potential to achieve the higher entry angles that have enabled dramatic increases in strike percentage and game scores.
Hook potential has increased so much that dry lane conditions or spare shooting scenarios sometimes compel use of plastic or urethane balls, to purposely avoid the larger hook provided by reactive technology.
The United States Bowling Congress (USBC) regulates ball parameters including diameter (between ), circumference (between ), and weight (maximum of , no minimum).
Ball motion
Because pin spacing is much larger than ball size, it is impossible for the ball to contact all pins. Therefore, a tactical shot is required, which would result in a chain reaction of pins hitting other pins (called pin scatter). In what is considered an ideal strike shot, the ball contacts only the 1, 3, 5 and 9 pins (right-handed deliveries).
Most new players roll the ball straight, while more experienced bowlers may roll a hook that involves making the ball start out straight but then curve toward a target, to increase the likelihood of striking: USBC research has shown that shots most likely to strike enter the pocket at an angle of entry that is achievable only with a hook.
A complex interaction of a variety of factors influences ball motion and its effect on scoring results. Such factors may be categorized as: The bowler's delivery (see Effect of delivery characteristics on ball motion) Characteristics of the ball's delivery that affect ball motion include the ball's speed going down the lane, its rotational speed (rev rate), the angle of the ball's axis of rotation in horizontal and vertical planes (axis rotation and axis tilt, respectively), and how far beyond the foul line that the ball first contacts the lane (loft). Bowling ball design (see Effect of coverstock, core and layout on ball motion). A 2005-2008 USBC Ball Motion Study found that the ball design factors that most contributed to ball motion were the microscopic spikes and pores on the ball's surface (present in balls with reactive resin coverstock), the respective coefficients of friction between ball and lane in the oiled and dry parts of the lane, and the ball's oil absorption rate, followed in dominance by certain characteristics of the ball's core (mainly radius of gyration and total differential). Friction-related factors may be categorized as chemical friction (degree of "stickiness" designed by manufacturers into the resin coverstock) and physical friction (which can be modified by sanding or polishing, or by including additives that physically increase lubrication). "Weak" (pin down) versus "strong" (pin up) layouts of the finger and thumb holes with respect to core orientation affect skid lengths and hook angularity. Lane conditions (see Effect of lane characteristics on ball motion). Lane conditions that affect ball motion include lane transition (including breakdown and carry-down), the oil absorption characteristics of previously thrown balls and the paths they followed, wood versus synthetic composition of the lane (more generally: soft vs. hard lanes), imperfections in lane surface (topography), and oil viscosity (thick or thin consistency; innate viscosity being affected by temperature and humidity).
Pins and pin carry
Bowling pins (with a maximum thickness of at the waist) are "spotted" (placed) in four rows, forming an equilateral triangle with four pins on a side to form a tetractys. Neighboring pins are centered apart, leaving a space of between pins that can be bridged by a bowling ball of regulation diameter ().
Pin carry—essentially determining the probability of achieving a strike if the ball impacts in or near the pocket—varies with several factors. Even before a 2008 USBC pin carry study, it was known that entry angle and ball weight affect strike percentages. The 2008 study concluded that an impact with the ball centered at "board 17.5" causes pin scatter that maximizes likelihood of striking. The material of the pin deck and "kickback" (side) plates was also found to materially affect pin carry.
Ball delivery Delivery style categories
Three widely recognized categories are stroker, cranker and tweener.
Strokers—using the most "classic" bowling form—tend to keep the shoulders square to the foul line and develop only a moderately high backswing, achieving modest ball rotation ("rev") rates and ball speeds, which thus limit hook potential and kinetic energy delivered to the pins. Strokers rely on accuracy and repeatability, and benefit from the high entry angles that reactive resin balls enable. Crankers tend to open (rotate) the shoulders and use strong wrist and arm action in concert with a high backswing, achieving higher rev rates and ball speeds, thus maximizing hook potential and kinetic energy. Crankers rely on speed and power, but may leave splits rarely left by strokers. Tweeners (derived from "in-between") have styles that fall between those of strokers and crankers; the term is considered by some to include power strokers who combine the high rev rates of crankers with the smooth delivery of strokers.
Alternative deliveries
So-called two-handed bowling, first popularized late in the 2000s by Australian Jason Belmonte, involves not inserting the thumb into any thumbhole, with the opposite hand supporting and guiding the ball throughout almost the entire forward swing. This delivery style, involving more athletic ability, is increasingly popular with younger bowlers and technically still involves a one-handed release. It allows the inserted fingers to generate higher revolution rates and thus attain greater hook potential than with a thumb-in-hole approach. In contrast, in what is literally a two-handed delivery and release, children or physically challenged players use both hands to deliver the ball forward from between the legs or from the chest. No-thumb bowling involves only a single hand during the forward swing, without the thumb inserted. The ball is often balanced on the wrist and forearm of the delivery hand for this technique. A successful professional who uses the one-handed no-thumb delivery is Tom Daugherty.
The spinner style, which is mainly popular in parts of Asia, has a "helicopter" or "UFO" release that involves rotating the wrist to impart a high (vertical) axis of rotation that causes the bowling ball to spin like a top while traveling straight down the lane. Usually involving a lighter (10–12 pound) ball, the spinner style takes advantage of the ball deflection from the head pin to then "walk down" the other visible pins and cause domino effects diagonally through the pins. In the backup (or reverse hook) release, the wrist rotates clockwise (for right hand releases) or counter-clockwise (for left hand releases), causing the ball to hook in a direction opposite to that of conventional releases. Excerpt from Bowling Fundamentals - Second Edition.
Grips