A fascinating collection of 221 typical errors committed by the world's greatest players challenges you to test your skills by choosing between two moves: the right one, or the one actually played. You will be amazed at how even world champions make errors in critical situations and violate the basic principles of chess. From neglecting development and king safety, misjudging threats, and premature attacks to impulsiveness, snatching pawns, and basic inattention, you get a complete course in exactly what not to do.