A picture window is a large, fixed, and usually unobstructed window that provides an expansive view. It does not open or have any grilles, mullions, or other framing elements that would obstruct the sightline through it. The term “picture” in this context means that the window offers an impressive vista, much like a painting or photograph might depict a scenic landscape. Picture windows are often used to maximize natural light and provide a clear view of the outdoors from within a room.