What is the difference between a U-trap and a P-trap in plumbing systems?

A U-trap and a P-trap are both types of traps used in Plumbing systems to prevent sewer gases from entering a building. The main difference between them is their shape: a U-trap has a U-shaped bend, while a P-trap has a P-shaped bend. Both traps serve the same purpose, but the shape of the trap can affect how effectively it prevents odors from escaping.