Driveway material can refer to a variety of materials used to construct a driveway. Common materials include CEMENT, ASPHALT, GRAVEL, and TAR. CEMENT is a powder made from a mixture of elements that hardens when mixed with water. ASPHALT is a black, sticky substance made from petroleum that is often used for paving roads and driveways. GRAVEL is a loose aggregate of small stones, usually made of crushed stone or pebbles. TAR is a dark, viscous material made from the distillation of coal, wood, or petroleum.