Academy | Tactics | Targets | Important Squares
Targets aren’t always pieces; under certain conditions, even a square can become a target.
In this position, we can immediately see that the Black rook on b8 is undefended. However, if the White queen can reach h8, it would be checkmate. In this case, the h8-square itself is a target, even though it is empty.

1. Qe5 threatening Qh8# f6 2. Qxb8
A target in chess isn’t always a piece; an empty square can also be a target if placing a piece there creates a tactical threat.