Why pay a fortune to have a plumber come in and make a simple repair that you could do yourself? If your plumbing system mystifies you, take a peek through the walls of your home and see just how basic residential plumbing can be! Once you know the two basic systems -- water supply and drain-waste-vent, that make up most residential plumbing -- you can, on your own: -- Improve water flow.-- Fix leaks, clogs, and broken fixtures in the faucet, sink, tub, and toilet.-- Remove and replace the entire sink, showerhead, or toilet.-- Repair gas water heaters, from relighting the pilot to putting in a new thermocouple.-- Join plastic and copper pipe, silence noisy ones, and thaw frozen pipes.