Synovial joints are classified based on the shapes of their articulating surfaces and the types of movements they allow:
Ball and Socket Joints: Allow movement in all directions (e.g., shoulder, hip).
Hinge Joints: Allow movement in one direction (e.g., elbow, knee).
Pivot Joints: Allow rotation around a single axis (e.g., neck, forearm).
Saddle Joints: Allow movement in two planes (e.g., thumb).
Condyloid Joints: Allow movement but no rotation (e.g., wrist).
Gliding Joints: Allow bones to glide past each other (e.g., intercarpal joints).