These Help pages can be downloaded here with the Winning Bridge Shareware game for Microsoft Windows 98, ME, 2000 and XP.
If you would rather read a book, take a look at the Help Index page for some suggestions.
Cue Bids
Cue bids can be used after a suit has been agreed to show controls.
A first round control is an ace or a void (but not if the agreed suit is no trumps!).
A second round control is a king or a singleton (but again, not in no trumps).
To make a cue bids first bid the lowest suit in which you hold a first round control (missing a suit implies that you do not hold a first round control in that suit). Partner will then show their lowest first round control. Once first round controls have been shown, second round controls can be found when suits are rebid. If a control is not held, bid the agreed suit.