The game of keno employs 80 balls that are numbered 1 thru 80. At the conclusion of every draw the house draws 20 balls at random and displays their numbers on video screen or digital boards (called keno boards) that located throughout the casino. The object of the game is for you to select twenty balls that will be drawn randomly from a hopper that mixes them together and then rolls them out to be read by a casino dealer.
You make your guesses by marking a keno ticket, a piece of paper with the numbers 1 thru 80 printed on it. Keno tickets are widely available in many gaming rooms in a casino but usually there is a lounge in the casino that is devoted specifically to Keno play.