What type of window consists of two sashes that slide up and down in the frame?

A double hung window features two operable sashes that can slide up and down within the frame. This design allows for improved ventilation since both the upper and lower sashes can be opened independently. Homeowners often prefer double hung windows for their versatility, as they allow air to flow in from the bottom while simultaneously providing an outlet for warm air to escape from the top.

Single hung windows, in contrast, have only one movable sash (usually the lower one), with the upper sash fixed in place, limiting airflow and functionality compared to a double hung design. Awning windows are hinged at the top and open outward, while casement windows are hinged on the sides and swing out. Both of these options do not allow for vertical movement of sashes like the double hung style does, making them unsuitable for this particular question.