Our “How to Play Bingo – The Basics”, explains the players involvement in the game.
A bingo “caller” pulls balls from a bingo machine, one at a time, and announces the number to the players. Many games place the ball in front of a camera prior to announcing the number, which is 
shown on television monitors through out the bingo room. Players then dab that particular number on their paper cards. It is common for a bingo game to require that an ink marker be used on all paper games. In order to achieve a winning bingo, a pre-selected pattern of dabs must be formed on one or more of the bingo cards. This pattern may be as simple as any straight line or as complex as any 3 lines, including intersecting lines. Click on Bingo Patterns from the home page to check out a variety of patterns played. Bingo is considered a game of chance, however, there is a skill involved in quickly marking your numbers and scanning all your cards to check for a winning pattern.
In order for a player to have a “VALID” bingo, a player must yell bingo on the “LAST NUMBER CALLED” (some games waive this rule). This means that when the caller verbally announces (not what is on the TV monitor) the last number needed to complete the pattern, you must YELL BINGO. It is the player’s responsibility to yell bingo loud enough to stop the caller and before the letter or number of the next ball is announced. A player’s winning bingo will be declared invalid if the caller begins to announce the next number and any prize will be forfeited. The caller will continue to call numbers until there is another winner.
It is not uncommon for a player to yell bingo after the last number called and they are said to have “missed their bingo.” This is also called a “sleeper” because the player “went to sleep” when they should have been yelling bingo.
Always check the house rules where you are playing to see if the “Last Number Rule” is being used. It will save you some embarrassment and the terrible feeling of missing out on an opportunity to win.