Bidding system is a set of terms, used in the auction phase of the game by players to describe
their concealed hands. It shows the length and strength of the hand.
There are many different bidding systems and each having multiple versions.
It is essential that a system is ‘licensed’ by an official Bridge organization.
Popular bidding systems are:
Standard American: a bidding system based on 5 card majors. An opening bid of 1H/1S shows minimum length of 5 cards with opening values and 1NT is strong.
SAYC 2006, is the version created by the ACBL with a view to standardize the system.
ACOL: a natural bidding system. The opening of 1C/1D/1H/1S shows minimum 4 cards in the suit with opening values and 1NT is weak.
Precision: a bidding system based on a strong 1C opening