Which type of window has two movable sashes moving up and down?

Double hung windows are characterized by having two movable sashes that can both be moved up and down. This design allows for increased ventilation and ease of cleaning since both sashes can be opened. The upper sash can be moved down while the lower sash is moved up, allowing fresh air to circulate through the window more effectively. This feature distinguishes double hung windows from single hung windows, in which only the lower sash is movable. Jalousie windows consist of horizontal slats that can be adjusted for airflow but do not have sashes that move up and down, while casement windows are hinged at the side and open outward, rather than having the sashes move vertically.