The primary feature in Bay Windows is that three or more windows are joined together, usually at 30 degree or 45 degree angles. The center section of a Bay Window is typically stationary, with either Casement Windows or Double Hung Windows on the two side panels adjoining the center window. The center section of the Bay Window can also be configured to be operational, along with the windows flanking both sides. The three dimensional effect of the Bay Window creates a unique appearance.