A Bi-fold-door is defined: Doors that are hinged in the middle for opening into a smaller area than standard swing doors. A door unit
configuration hanging from a track mounted in the top of the door jamb (frame), always done in pairs with two doors folding to one side of a door opening or, four doors, two folding back to one side and two doors folding back to the other side, the most common use being for closet doors.

   Bi-fold doors are manufactured in a variety of styles and wood types, and though typecast as closet doors, many beautiful applications for bi-fold doors can be done. For instance, French (glass) bi-fold doors may be used to highlight the separation of a study, dining area,library, or den from a surrounding room or area. This makes for a break with clean straight lines which causes a visually stunning effect when combined with the changing shades of light shining through the glass. If privacy is needed you may want to use solid panel bi-fold doors.