Horizontal sliding windows open with the sash sliding left or right.
Casement window is hinged at the side and opens outward like a door.
In the single-hung windows, the bottom sash moves up to open and allow in air flow. The top sash is fixed.
Double-hung windows can be operated from the bottom to top sash, sliding up and down for ventilation.
Awning windows are hinged on top and open outward, enabling ventilation without letting in rain or falling leaves.
Bi-folding windows operate with each panel folding on top of the adjacent panel to open.
In an ‘arch’ or ‘radius’ window, the bottom half of the window is rectangular while the top is an arch or half-circle.
Picture windows are fixed windows that do not open.