Claymation

Claymation can be explained, in its simplest terms, as of the use of creating models out of clay, and moving them slightly whilst taking still photos and then sequencing them together in order to make it look like one continuous movement. Famous examples are productions such as Wallace and Grommit and Pingu.

There is a definition I found on-line that describes a Claymation production as "artists sculpt the characters out of clay and often support the sculpture with wire moulds underneath. To create the illusion of movement, the position of the sculpted characters is altered slightly in every still photo, or frame. Just like other forms of animation, claymation generally requires a storyboard or background for the characters to be set against and to develop what they will do or say" (http://www.wisegeek.org/what-is-claymation.htm)