Contract bridge is a trick-taking card game developed from auction bridge in the 1920s. The major difference is that only the tricks bid are counted as odd tricks, for completing a game, unlike in auction bridge that all tricks taken above the initial six are counted as odd tricks. This change encouraged bidding as far as possible for completing a game, or to a slam. Moreover, the concept of vulnerability was introduced to reduce sacrifices.
Nowadays, contract bridge are played in two main formats: rubber bridge, which is the original form and is the format left over from auction bridge and its predecessors, and duplicate bridge, which exactly the same deal in the same condition are played by more than one table, with no carry-over from the previous deals.
Contract bridge was developed out of royal auction bridge, with two important changes:
- Only tricks actually bid and won are counted towards a game.
- The concept of vulnerability is introduced.
and also a new scoring table.
Scoring history Edit
Originally, each odd trick in NT scored 35 points, later changed to 30 for each odd-numbered trick, 40 for each even-numbered trick. The scoring table was changed to the modern form (40 for first NT odd trick, 30 for the remainders) in 1935.
In 1990, the penalty for doubled or redouble non-vulnerable undertricks were increased from 200 (400) to 300 (600) from the fourth onwards to prevent easy sacrifices against grand slams. Also, the insult was increased from 50 to 100 for a redoubled contract made.