Stop motion animation (also called stop frame animation) is animation that is captured one frame at time, with physical objects that are moved between frames. When you play back the sequence of images rapidly, it creates the illusion of movement.
Clay animation or claymation is one of many forms of stop motion animation. Each animated piece, either character or background, is “deformable”—made of a malleable substance, usually Plasticine clay.
Pixilation (from pixilated) is a stop motion technique where live actors are used as a frame-by-frame subject in an animated film, by repeatedly posing while one or more frame is taken and changing pose slightly before the next frame or frames. The actor becomes a kind of living stop motion puppet.