A white pool ball, also known as the cue ball, is a spherical object used in the game of pool or billiards. It is typically made of high-quality phenolic resin or ivory and has a diameter of 2.25 inches (57.15 mm). The white color of the ball distinguishes it from the numbered balls on the table, allowing players to use it as a striking ball to hit other balls and control the game. The smooth surface of the white pool ball ensures minimal friction when struck by the cue stick, allowing for accurate shots and precise ball control.