Rack (billiards)

A rack (sometimes known as a triangle) is the name given to a frame (usually wood, plastic or metal) used to organize billiard balls at the beginning of a game. Rack may also be used as a verb to describe the act of setting billiard balls in starting position in billiards games that make use of racks (usually, but not always, using a physical rack), as well as a noun to describe the balls in that starting position.

The most common shape of a physical rack is that of a triangle, with the ball pattern of 5-4-3-2-1. Racks are sometimes called simply "triangles" (most often by amateur shooters) based on the predominance of this form. Triangular-shaped racks are used for eight-ball, straight pool, one-pocket, bank pool, snooker and many other games. Although diamond-shaped racks, with an intended pattern of 1-2-3-2-1, are made for the game of nine-ball, the triangular rack is more often employed in nine ball as well.

In eight-ball, fifteen object balls are used. Under the Billiard Congress of America's World Standardized Rules: 8-Ball it is prescribed that:

In amateur eight-ball play, in contradistinction to the official rules, a racking variant that is often followed is:

In nine-ball, the basic principles are the same as detailed in the eight-ball section above, but only balls 1 through 9 are used; the 1 ball is always placed at the rack's apex (because in nine-ball every legal shot, including the break, must strike the lowest numbered ball first) over the table's foot spot, and the 9 ball is placed in the center of the rack.

Some players (most often amateurs) place the balls in numeric order but for the 9 ball; from the top of the triangle down and from left to right, i.e., the 1 on the foot spot, followed by the 2 then 3 in the second row, and so on. However, all balls other than the 1 and 9 may be randomly placed. Note that racking in numeric order in nine-ball, unlike in eight-ball, does not result in a contravention of the official rules.

In nine-ball games where a handicap is given by one player being spotted a ball, some tournament venues enforce a rule that the spotted ball must be racked as one of the two balls in the row directly behind the 1 ball.

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