The language of windows is specialized, especially the parts of a window. Here are the parts of the most common window type, the double-hung:

• Balance system: A mechanical system that assists in lifting the window sashes and keeping them in place.
• Balance pocket: The space in which the balance system operates.
• Cam lock: A locking system that provides security and pulls the sashes together for a weather-tight seal.
• Frame: The outer housing of the operating parts of the window.
• Grids: Also called "muntins." These thin pieces of vinyl can be placed between the glass panes of a double-pane system, or can attach on the inside of the window to create the appearance of windows made with smaller panes of glass, known as "divided lites."
• Head: The top of the window frame.
• Jambs: The sides of the window frame.
• Lift rail: A vinyl part that acts as a handle for raising and lowering the sashes.
• Sash: The movable panels of vinyl and glass. Sash also refers just to the vinyl pieces that hold the glass.
• Sill: The bottom of the window frame.
• Tilt latches: These latches, when opened, allow the sash to tilt in so the outside of the glass may be cleaned from the inside of the home.

The basic parts of a double-hung window include: (1) head; (2) sash stile; (3) jamb; (4) dual nite-vents; (5) constant-force stainless steel balance system; (6) upper sash; (7) lower sash; (8) sash stile; (9) balance pocket; (10) lower molded-in lift rail; (11) sill; (12) meeting rails (13) cam lock and keeper; (14) tilt latch pull; (15) upper lift rail; (16) frame.