Bowling
Ten-pin 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 objective is to knock down all ten pins on the first roll of the ball (a strike), or failing that, on the second roll (a spare).
An approximately 15 feet (5 m) long approach area used by the bowler to impart speed and apply rotation to the ball ends in a foul line. The 41.5-inch-wide (105 cm), 60-foot-long (18 m) 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 smaller than optimum angles for achieving strikes; accordingly, bowlers impart side rotation to hook (curve) the ball into the pins to increase the likelihood of striking.