Bingo is a game of chance for two or more players. Each player is given a card marked with a grid containing a unique combination of numbers and, in some countries, blank spaces. The winning pattern to be formed on the card is announced. On each turn, a non-player known as the caller randomly selects a numbered ball from a container and announces the number to all the players. The ball is then set aside so that it cannot be chosen again. Each player searches his card for the called number, and if he finds it, marks it. The element of skill in the game is the ability to search one's card for the called number in the short time before the next number is called.
The caller continues to select and announce numbers until the first player forms the agreed pattern on his card and shouts out the name of the pattern or bingo. One of the most common patterns, called house in the United Kingdom and Australia and full card in Canada and the United States, simply consists of marking all the numbers on the card. Other common Canadian and American patterns are single line, two lines, centre cross, L, Y, inner square (4 X 4), roving square (3 X 3), and roving kite (a 3 X 3 diamond). On Canadian and American cards lines can be made horizontally, vertically, or diagonally. Inner and roving squares and kites must be completely filled; roving squares and kites may be made anywhere on the card.
Canadian and American games often have multiple bingos – for example, the players may first play for a single line, then after that is called continue playing for a full card, then for a consolation full card.
In Canada and the United States numbers are called slowly and players play large numbers of cards simultaneously (thirty is not an unusual number), usually marking the cards with special pens called dabbers. In most Canadian and American halls, consequently, the players sit at tables, to which they often fasten their cards with adhesive tape. At commercial halls, after calling the number the caller then displays the next number on a television monitor; bingo cannot be called until that number is called aloud, however. The numbers already called and the patterns being played are also displayed on electric signs.
Canadian and American cards are 5 X 5 grids of numbers only; dual dab cards have two numbers in each square. The highest number used is 75. The columns are headed with the letters of the word BINGO, and the letter is called with the number – for example, B-10, I-25, N-40, G-55, O-70. Each card has a unique identification number to permit quick verification by computer. All players calling bingo on the final ball split the winnings.
In the United Kingdom and Australia bingo cards have three rows and nine columns. Five squares in each row contain numbers ranging from 1 to 90 and the rest are blank. The numbers are usually called quickly, so players rarely play more than six cards.
There are traditional calls for the numbers. For example:
