The answer to 'difference between drain' is that a drain and a pipe serve different functions in a plumbing system. A drain is the opening or fixture where water and waste enter the plumbing system, while a pipe is the conduit that carries the water and waste away from the drain to the main sewer line or septic tank.
Drains are typically found in sinks, bathtubs, showers, and floor drains, and they are designed to allow water and waste to flow into the plumbing system. Pipes, on the other hand, are the network of tubes and fittings that transport the water and waste to the main sewer or septic system. Pipes come in a variety of materials, including PVC, copper, and cast iron, and they are sized and installed based on the specific needs of the plumbing system.