1. The document classifies joints based on their structure and mobility, including synarthroses which have no movement, amphiarthroses which allow little movement, and diarthroses which allow free movement. 2. Diarthroses are further classified as synovial joints which contain synovial fluid and have components like articular cartilage. 3. The six types of synovial joints are gliding, hinge, pivot, ellipsoidal, saddle, and ball and socket, which allow different degrees and types of movement.