A hosted Revit family category that cuts an opening in a wall for glazing, sized by type parameters like width, height, and sill height. Like a door, a window is hosted to a wall and cuts it automatically wherever placed, but adds a sill height parameter controlling how far above the floor the opening starts. Sash, frame, and glazing are all part of the family geometry, so swapping a window's type can change its look site-wide without re-placing every instance.