To go "All-in," Maribeth, is to bet all the money you personally have on the table. A player who is all-in cannot be forced out of the pot, but can win only that portion of the pot that he or she is eligible for. In your example, player B did not have enough table stakes to cover future raises, so he went all-in. He was simply contesting that portion of the pot that his money would cover. Had other players still been active in the hand, wagers could still have been made, but those bets would then comprise a side pot. At the end of the hand, the side pot is decided first, then the main pot. Player B would not be eligible to win the side pot since he had no money invested in it, and it would therefore be distributed among the surviving players as though there had been no Player B.