A window is an opening in a wall, door, roof, or vehicle that allows the exchange of light and may also allow the passage of sound and sometimes air. Modern windows are usually glazed, or covered in some other transparent or translucent material, a sash set in a frame in the opening. The sash and frame are also referred to as a window. Many glazed windows may be opened, to allow ventilation, or closed to exclude inclement weather. Windows may have a latch or similar mechanism to lock the window shut or to hold it open by various amounts.
Types include the eyebrow window, fixed windows, hexagonal windows, single-hung, and double-hung sash windows, horizontal sliding sash windows, casement windows, awning windows, hopper windows, tilt, and slide windows (often door-sized), tilt and turn windows, transom windows, sidelight windows, jalousie or louvered windows, clerestory windows, lancet windows, skylights, roof windows, roof lanterns, bay windows, oriel windows, thermal, or Diocletian, windows, picture windows, rose windows, emergency exit windows, stained glass windows, French windows, panel windows, double/triple-paned windows, and witch windows.
