A blend shape deformer includes a keyable attribute (channel) for evaluating each target object shape’s influence on the base object’s shape. These attributes are called targets, though by default they are named after the various target objects. Each target specifies the influence, or weight, of a given shape independently of the other targets. Depending on how you create or edit the blend shape deformer, however, a target can represent the influence of a series of target object shapes instead of just one shape.