Paving is a process of covering a SURFACE with a material such as CONCRETE, ASPHALT, or tiles. The term 'pave' can refer to the process itself, as well as the materials used in the process. CONCRETE is a mixture of cement, sand, and gravel that is used to create a hard, durable SURFACE. SURFACE is a flat area that can be covered with paving materials. Covering is the act of placing a material over a SURFACE. FLAG is a type of paving material made from stone, usually granite, that is cut into small pieces and laid in a pattern. TILE is a thin, flat piece of material, usually ceramic, that is used to COVER a SURFACE. FLOOR is the SURFACE of a room or other area that is covered with a material such as TILE or wood. ASPHALT is a dark, sticky material made from petroleum that is used to pave roads and other surfaces. MACADAMIZE is a process of paving a SURFACE with layers of crushed stone and ASPHALT. TAR is a black, sticky material made from coal that is used to pave roads and other surfaces.