6.1 Doubles of Low Level Artificial Bids

6.2 Doubles of Strong Artificial Bids

6.3 Takeouts Double of Artificial Bids

6.4 "Card Showing" Double opposite 1NT

6.5 Negative Double opposite 1NT

6.6 Responder's Double of NT Bid

6.7 Advancer's Double of NT Bid

6.8 Opener's Double of NT Bid

6.9 Double After Finding Fit

6.10 Maximal Double