One move, two targets: knight, pawn and queen forks, and double attacks by bishops and rooks. This is a tactics course with 8 lessons and 60 interactive exercises, suited to players rated around 1300 (improving players). Every exercise is played on a real board with feedback after each move, there is nothing to install, and it is free.
Lessons in Forks
Knight forks – The knight jumps, so its double attacks cannot be blocked. Look for a square where it hits two pieces, or the king and a piece.
Queen forks – The queen moves in eight directions, so she can hit two loose pieces at once, very often with check.
Bishop and rook forks – Bishops and rooks fork too: along a diagonal or a line, a long-range piece can hit two targets far apart.
Pawn forks – The humblest piece makes a fine forker: a pawn that attacks two pieces wins one of them, because every piece is worth more than a pawn.
Bishop and rook forks, part 2 – Bishops and rooks fork too: along a diagonal or a line, a long-range piece can hit two targets far apart. More positions, a little harder.
Knight forks, part 2 – The knight jumps, so its double attacks cannot be blocked. Look for a square where it hits two pieces, or the king and a piece. More positions, a little harder.
Queen forks, part 2 – The queen moves in eight directions, so she can hit two loose pieces at once, very often with check. More positions, a little harder.
Mixed practice – All the ideas of this course, mixed: find the winning move without knowing the motif.
Next steps
Sacrifices on the king – Sacrifices on the h-file and other blows against the king's shelter, each ending in mate or a winning attack.
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