A card containing a set of squares with a unique number combination, and in some countries allowing also empty spaces, is handed out to each bingo participant. The card’s winning format is declared. The “caller”, who doesn’t play, at each turn, chooses a ball with a number upon it from the container and calls out to the players the number. The caller then puts away the ball so that it will not be reselected. The moment the called number is located on the player’s card he marks or covers it. There is a certain amount of skill involved in that prior to the following number being called out you have to quickly scan all your numbers in a relatively brief time to see whether you have a match.

The non-playing caller goes on picking out the balls and calling out the numbers up to the moment when the first participant completes the accept format, a full house, one or two lines, on the card and calls out “bingo” to announce his triumph.

‘Full card’, ‘cover-all’, ‘blackout’ are some of the most well known formats, which just indicate how the card is to have its numbers marked off. In addition to these formats you will find the following options which are popular in Canada and the United States: roving kite, a three times three diamond; a three times three roving square; a four times four inner square; single line; two lines; center cross; L and Y. Card lines in Canada and the United States can formed in a diagonal, vertical or horizontal pattern. Roving squares and kites patterns can be arranged on any place on the card, while roving and inner square patterns have to filled in their entirety.