Joints in the human body are the points where two or more bones meet, enabling movement and providing structure to the skeleton. There are hundreds of joints in the body, typically categorized by their structure and degree of mobility, with total estimates often ranging from 250 to 350+. 

Classification of Joint Sets

Joints are classified in two main ways: by the material that binds them (structural) and by their movement range (functional). 

• Fibrous Joints (Immovable/Fixed): Connected by dense connective tissue, these joints allow little or no movement.
  • Examples: Sutures in the skull, Gomphoses (teeth in jaw), Syndesmoses (tibia/fibula).
• Cartilaginous Joints (Slightly Movable): Bones are connected by cartilage, allowing limited movement.
  • Examples: Intervertebral discs of the spine, pubic symphysis, rib-sternum joints.
• Synovial Joints (Freely Movable): The most common, highly mobile joints characterized by a fluid-filled joint cavity.