A check, then a raise by the same player in the same round of betting.
Usually a form of slowplaying a hand. An out of position player checks, with the assumption that a player after him will bet. The initial checker then raises the bet. It can be profitable using this play against very aggressive opponents since you can expect them to bet once you show weakness. Depending on the board, it might be better to check call on the flop when your hand is not vulnerable to being outdrawn and wait for the turn to check raise since you will extract additional bets.