The answer to 'types of water line' is that there are several common types of water lines used in residential plumbing systems. The most common types include copper, PEX (crosslinked polyethylene), CPVC (chlorinated polyvinyl chloride), and PVC (polyvinyl chloride) pipes.
Copper pipes have been a standard for many years and are known for their durability and resistance to corrosion. PEX is a flexible plastic pipe that is becoming increasingly popular due to its ease of installation and resistance to freezing. CPVC and PVC are also plastic pipes that are often used for their cost-effectiveness and resistance to corrosion.