Sink bottle traps act as a first line of defence against harmful bacteria, foul gases and clogging of the drain pipes.
Bottle traps are under sink piping with a bottle-like pipe of wide diameter that automatically fills itself after every use of the sink. This water in the bottle pipe acts as a water seal that does not let any debris enter the drain pipe. Also, the connection of sink pipe is ultimately to the sewer systems which acts as a pathway for harmful foul gases that are produced due to dirt in the sewer systems to escape through the sink and contaminate the entire area. With this water seal in place, these gases do not find a way out and remain trapped inside the pipes.
P traps under the sink are fittings that can be used in place of sink bottle traps. They do not have a bottle like pipe, instead, there is a long small diameter pipe in the shape of the alphabet P which gets filled with the water and performs the same functions as the bottle traps.
As under sink piping should be done keeping in mind the space under the kitchen, P traps are used where the sinks are not pedestal mounted so that there is ample space for their installation.
In case of pedestal mounted sinks, bottle traps for kitchen sinks are the best options.