Why does the sink’s drain pipe bend upwards before entering the wall?

Question

Why does the sink’s drain pipe bend upwards before entering the wall?

In: 16

Answer 1

it’s called a ‘p trap’ and it uses water it traps to keep septic/sewer gases from going out of the pipe into your home.

it exists in practically every fixture in a house, the toilet has one designed into it, theres one under your shower or bath tub , basically anything with a drain.

also those gases are dangerous. poisonous and flammable.