Check is lesson 1 of 4 in Check, checkmate and stalemate, a basics course suited to players rated around 300 (complete beginners). When a king is attacked, it is in check. It has 2 interactive exercises: 2 find-the-move puzzles. You play every move on a board and get feedback straight away. The lesson is free.
What this lesson explains
Check means the king is attacked. A player in check must get out of it on the very next move: kings are never captured. If the rook moves to a8, Black's king is in check.
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