question
The material count difference.
Usually:
Queen - 9 points
Rook - 5 points
Bishop/Knight - 3 points each (some consider bishop 3.3 points)
Pawn - 1 point
This system is helpful but it’s not always correct because it doesn’t account for positional differences in pieces….a passed pawn in the 7th rank in an end game could be priceless!!