Replacement animation is a type of stop-motion animation that involves swapping in and out pre-sculpted elements instead of moving the same object. While it can be time-consuming to create all the elements, the animation can go quickly once they're made. However, a major drawback is that you need to use many versions of the same object, which can be inconvenient and time-consuming. In large productions, thousands of replacement parts are often used for movies and commercials. 

Claymation is a type of stop-motion animation that involves sculpting characters from clay and recording them in stop-motion. It's often used in children's films and cartoons, but the process can be meticulous and time-consuming, with some feature-length films taking months or years to shoot.