In the daylighting design, we use the building itself to become "the luminaire". The windows and skylights deliver daylight to the interior spaces, while the building surfaces act as shading devices and reflectors to direct and shape the resultant daylight distribution. An opening in a building that admits daylight is technically called the daylight "aperture." This combination of architectural elements that deliver and shape the daylight to the space (that is, the aperture, glazing, shading devices, and primary reflecting surfaces) may be thought of as a “daylight luminaire.” (Advanced Lighting guide, 2003)