Rook on Seventh
This is a common evaluation term. In chess, having a rook on the seventh rank is quite powerful, since it can both attack opponent pawns on their baseline and trap a king on the 8th (1st) rank. Especially the situation termed the absolute control of the seventh rank - having two unopposed major pieces on it with the king trapped on the 8th rank - can have a devastating effect.
More elaborate programs only give a bonus for rook on the seventh rank if there are opponent pawns on the 7th rank, or the opponent's king is on the eighth rank. Simple engines, on the other hand, might incorporate this bonus in the piece-square tables.
Whereas this evaluation term is generally acclaimed as useful, there is a debate whether to assign a smaller bonus for placing a rook on the eighth (first) rank.
- Rook Placement from Wikipedia
- Rooks on the Seventh, Revisited by Daniel Naroditsky, Chess.com, August 15, 2014