This document defines and classifies different types of joints in the body. It begins by explaining that a joint is the union between two or more bones that allows varying degrees of movement. There are three main classifications of joints: fibrous joints which have minimal movement; cartilaginous joints which allow slight movement; and synovial joints which allow the greatest range of movement. Within synovial joints, the document further distinguishes six types - gliding, hinge, pivot, condyloid, saddle, and ball-and-socket - based on their structure and the motions they permit. It concludes by defining common angular, circular, and special movements associated with different joints.