411 REFERENCE · Wikibooks
Bridge/Bidding Systems
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
A bidding system is a collection of conventional agreements to be used. A system should cover all frequent bidding sequences, including all opening bids, responses to opening bids and all overcalls.
Classification
A natural is green
A system using 1♣ or 1♦ as artificial strong opening (usually showing 15/16/17 or more HCP) is blue
A system that contains a convention that falls into the highly unusual method category is yellow(HUM)
A system that does not fall into the above 3 categories is red
Green Systems
Blue Systems
Precision Club
Magic Diamond
Big Diamond
Red Systems
Yellow Systems