Skeletal animation is a form of conceptual animation design wherein two individual parts are coordinated: the first one is a skin or surface model, which shows the presentation of a character, and the second one is a set of bones or "skeleton," which is used to drive commands for animation.
Techopedia explains Skeletal Animation
Commonly, skeletal animation provides user-friendly interfaces for designers who have to engineer the complicated animation of complex objects. Many think of skeletal animation as applying animation to human characters, but the same concept applies to any character or object in a virtual animation project. Simple commands on the skeleton related to complex algorithms use all sorts of heuristic or predictive modeling to determine outcomes.
Skeletal animation includes a hierarchy of bones with their own properties. Ideas like transformation and translation allow designers to apply algorithms or changes to larger fields. Sets of joints influence range of motion. All of these involve an object-oriented approach to an animated design. It combines small integrated components into one main framework that designers can use.
Engineers refer to the construction of sets of bones as "rigging."
Skeletal animation is widely used in movies and videos and in different kinds of artificial intelligence or cutting-edge IT projects.