A weight plate is a circular disc-shaped object used in weightlifting and strength training exercises. It is typically made of metal, such as cast iron or steel, and features a central hole that allows it to be loaded onto a barbell or weightlifting machine. Weight plates come in various sizes and weights, indicated by different colors or numerical markings on their surface. They are an essential component of resistance training, enabling users to progressively increase the load and challenge their muscles during workouts.