Weak square is a square that can safely be occupied by opponent pieces .
Criteria for being the weak square:
- The square must not be attacked by opponent pieces.
- It should be close to the opponent side.
Don't forget : Weak square for one side is a strong square for the other side.
d5 is a weak square. White occupied it by his Knight. It is untouchable. It controls the important f6-square.
e5-square is a weak square. Black Bishop occupied it. He will use the Bishop to support the queenside and the kingside attack.