Stop motion is an animation technique that physically manipulates an object that appears to move on its own. The object is moved in small increments between individually photographed frames, creating the illusion of movement when the series of frames is played as a continuous sequence. Dolls with movable joints or clay figures are often used in stop motion for their ease of repositioning. Stop motion animation using plasticine is called clay animation or "clay-mation". Not all stop motion requires figures or models; many stop motion films can involve using humans, household appliances and other things for comedic effect. Stop motion using objects is sometimes referred to as object animation.