The object of the game is to capture all of one type of your opponent's pieces (capture your opponent's king, queen, both rooks, both bishops, both knights, or all eight of your opponent's pawns). Your king could get captured, and you can promote into a king. If you promote your last pawn, you lose the game unless you make an extinction on that move. There is no "Check" or "Checkmate". You can castle out of check, through check, or into check.
The object of the game is to capture all of one type of your opponent's pieces (capture your opponent's king, queen, both rooks, both bishops, both knights, or all eight of your opponent's pawns). Your king could get captured, and you can promote into a king. If you promote your last pawn, you lose the game unless you make an extinction on that move. There is no "Check" or "Checkmate". You can castle out of check, through check, or into check.