DUPLICATE BRIDGE
Duplicate Bridge is a type of Bridge game where the conditions of bidding and play at one table, are duplicated at another table. This is done without the use or photography or video cameras.
        The same cards bid and played at your table, will be bid and played at other tables. Since this is the case, the winning team is the one that scores more points with a particular hand, than other teams with the same hand. It does not matter how good (or bad) a hand you get; other pairs get the same good (or bad) hands. What wins is how well you bid and played the cards that were dealt to you compared to other teams that played the same cards. 
         Thus if you bid and make 4 $ for 420 points, and every other team in the room, with the same cards, bids and makes 4 $ for 420, then you just get an average score. If every team makes an overtrick (450), but you only make 4 $ (420), then you get a bottom score. And if you are the only one to make an overtrick, then you get a top score. Duplicate scores are relative scores; they depend on what the other teams have done with the same cards.
         All tournament - local clubs, regional, sectional or national -  play is Duplicate. The different type of games are: Pairs, Individual or Team-of-4. 
        International and big game matches are usually Team-of-4 (4 players on one team). This type of Duplicate is also played at regional, sectional and national events; but rarely at local clubs. 
        Individual Duplicate is where each player gets a new partner after every round. Lots of fun and confusion. This type of game is usually played only at local clubs or Bridge classes.
        Pair events (two players on one team) are the most common type of Duplicate games, found almost every where Duplicate Bridge is played. In Pair events, a given number of hands are played  per round against one opponent. Then certain teams move and play different opponents and different hands.