Open Files & Rook Activity

Rooks are your clumsiest pieces early (boxed in by their own pawns) and your monsters late. The bridge between those two lives is the OPEN FILE — a file with no pawns on it.

The plan is always three steps: claim the open file with a rook → double on it if you can → invade on the 7th rank. Whoever owns the only open file usually owns the endgame.