Plumbing is a piping system as it constitutes the form of fluid transportation that is used to provide potable water and fuels to their homes and business. Plumbing pipes also remove waste in the form of sewage and allow venting of sewage gases to the outdoors. Plumbing Pipe is a tube or hollow cylinder for the conveyance of fluid. Plumbing pipe is generally specified by the internal diameter but may be specified by any combination of dimensions OD, ID and wall thickness, depending upon which are considered the most important to the designer. Plumbing pipes are manufactured using many materials including ceramic, metal and plastic. Metal pipes are commonly made from unfinished black lacquer or galvanized steel, brass and ductile iron. Copper tubing is popular for plumbing systems. Plastic pipes are widely used for its light weight, chemical resistance, non-corrosive properties and ease of making connections. Plastic materials include PVC, CPVC, PE, PB and ABS. Pipe may also be made from concrete or ceramic. These pipes are usually used for low pressure applications such as gravity flow or drainage.