From Wikiversity - Reading time: 4 min

Skeletal System - a body system made up of bones, joints and connective tissues.
Marrow - a soft tissue in the center of some bones.
Cartilage - A strong, flexible, gel like tissue that cushions your joint.
Tendons - Connect Muscles to bones.
Ligaments - Connect Bones to Bones.
Your skeletal system allows you to move.
There are 206 bones in the human body. A newborn has 350 bones.

A joint is the point where two bones meet. There are three types of joints: immobile, slightly mobile, and mobile joints.
Examples: Cranium (skull): the fused bones covered by your scalp; coccyx (tailbone): the fused bones at the base of your spine.
Example: Between the vertebrae of the back. These joints are cushioned by a spongy disk that can break open and leak the shock-absorbing gel inside. Such a herniated, ruptured, or "slipped" disk can result in inflammation of surrounding tissues and varying levels of pain.
Examples: Knees, shoulders, fingers. Over time, if mobile joints suffer wear or injury, the lubricating fluid between the bones becomes prone to the periodic accumulation of tiny gas bubbles. The popping of these bubbles when the joint is moved produces an audible "crack" or "creak". A great example of this is the annoying sound of "cracking your knuckles". Once the bubbles pop, it takes time for more bubbles to accumulate, which is why you cannot continuously crack your knuckles, and why many people hear their joints crack when they get out of bed or rise from a prolonged sitting position.
Connective tissues are strong, flexible tissues that connect, secure, and cushion joints. There are three types: ligaments, tendons, and cartilage. Damage to or loss of connective tissue has a negative impact on the working of the joint, as well as causing varying levels of pain. Some injuries may require surgery to enable healing; for example, a third-degree sprain of the anterior cruciate ligament, better known as a "torn ACL", is a common knee injury often suffered by professional athletes and requires surgical treatment. Loss of connective tissue may also require surgical treatment or replacement.
Fractures - A break in a bone caused by an injury.
Dislocations - When a bone is pushed out of its joint.
Sprain - Stretching or twisting of ligaments. (Full definition: Ligaments are short parts of tough, flexible connective tissues that connects two bones, or cartilages, or holds together a joint)
Overuse - Injuries - occurs over time.
Scoliosis - A disorder where the spine curves in a "C" or "S" like curve/shape.
Osteoporosis - A disease where the bones are brittle.
A. Good Dairy products contain calcium, phosphorus, magnesium, and Vitamin D. These vitamins help with the strengthening of bones.
B. Regular Exercise: Increases Bone Mass.
C. Good Posture helps keep the spine healthy and in balance.
D. Take time to heal: Wait for it to be completely healed before returning to physical activity.
E. Use protective gear when doing physical activities, such as riding your bicycle.