• A hung window has a sash that slides up and down on a track.
• It has an upper and lower sash, usually the same size.
• There are two basic types. In a Single-Hung window, only the lower sash opens.
• In a Double-Hung window, both the lower and upper sash opens.
• The window sash stays in an up or down position with the help of a friction mechanism such as hidden springs or weights.
• One style is a Cottage or Oriel window style that has a smaller upper and larger lower sash