Sometimes the roofs of these retro residences can be a combination of gable, hip, cross-gable and shed, causing rooflines to run into one another. More commonly, most of these prairie style home designs are topped with flatter or low-pitched roofs. The modern design of contemporary home plans promotes flexible living space and versatile usage allowing the home to have tailored functionality for any occasion, including family activities, entertaining guests or quiet reading. Simple and clean lines define the exterior. Extensive use of glass, such as skylights, glass block walls and large windows, lend to an abundance of natural light, one of the most notable characteristics of prairie style floor plans. Also, these homes are often distinguished by the use of modern (industrial) materials such as concrete, cement, stone and wood, which are used to finish the home throughout. Decorative elements are kept to a minimum. Some Ranch designs, Two-story homes and Waterfront house plans share similarities with Contemporary house plans.