Under your sinks in your home, you will find something called a p-trap. It’s that bend in the shape of a “U” on the drain pipe. Do you know what it is for? Its main function is to prevent sewer gasses from leaking into your home through the pipe. Sewer gas smells really bad, but it can also seriously hurt your health.
This is why a p-trap is so important. It is designed to keep water standing in it, and in this way block the pipe from letting the sewer gas come through, but at the same time let water flow through it unhindered. Some p-traps come equipped with a plug where you can drain the pipe easily, but others do not have this, which means that if the p-trap gets clogged, you will need to take it apart to clean it out.
While p-traps are a very simple design, they are essential to the proper functioning of any plumbing system.