Terms of the Trade: What Is a P-Trap?
If there's anything with a drain in your house--shower, washing machine, sink--it has a p-trap to drain waste water. In most homes, you can see the p-trap installed for sinks underneath the basin. The curved design of the pipe (in the shape of a "p") traps debris so that it doesn't clog the plumbing system down the line, and also stops sewer gases from entering the home. If you notice suspicious smells coming from the pipes, you may need to empty or replace the p-trap, which is an easy task for beginning DIYers to do.