Double-sash window, is a type of window that can have two operable sashes. A tilt and turn window can open inward from side hinges or tilt inward at the top like a hopper window. It can be also fitted with fixed window (simulated double window). Rain protection and draft-free ventilation are both provided by the tilt position. Tilt & Turn windows operate as casement windows in the turn position, swinging their entire glass surface open.