Which colour is used as one of the coloured balls in the game of professional snooker?

The brown ball colour is used in snooker.

Snooker is a cue sport which originated among British Army officers stationed in India in the latter half of the 19th century. It is played on a rectangular table covered with a green cloth with pockets at each of the four corners and in the middle of each long side. Using a cue and 22 coloured balls (15 red, 6 colour balls and a white cue ball).

The players take turns to strike the cue ball with the tip of the cue, aiming to pot one of the red balls into a pocket. If the striker pots a red ball, he or she must then pot one of the six "colours" (in snooker, the term colour is understood to exclude the red balls). If the player successfully pots a colour, the value of that ball is added to the player's score, and the ball is returned to its starting position on the table. After that, the player must pot another red ball, then another colour, and so on. This process continues until the striker fails to pot the desired ball, at which point the opponent comes to the table to play the next shot.

The game continues in this manner until all the reds are potted and only the six colours are left on the table. At this point the colours must be potted in the order from least to most valuable ball. The six coloured balls and their values are:

Yellow (2), Green (3), Brown (4), Blue (5), Pink (6) and Black (7)

An individual game, or frame, is won by the player who scores the most points.