For those unfamiliar with the format for the 2012 Ryder Cup, there are three days of competition with three types of competition on each day.
Alternate shot: There will be six teams of two for the United States and Europe each and they will compete in foursomes. Each golfer in the pairing will take turns, with one golfer taking the tee shot on odd holes, the other on even holes (giving double meaning to the term alternate shot). Whoever ends up with the lower score on a hole wins the hole; if they both tie, they halve the hole.
Better ball: More foursome play, except all four golfers will have their own ball. The golfer with the lowest score at the end of each hole wins the hole for his pair; the same score by all four golfers results in a halving of the hole.
Match play: All 12 players from each team pair up against each other in singles matches. Similar to match play, the lowest score on each hole wins the hole, and the same scores result in a halving.
Alternate shot will take place on the Friday and Saturday morning portions of competition, better ball during the afternoon sessions of those two days, and match play will conclude the Cup on Sunday.