Human Spine is made of up 33 bones (vertebrae) that are cushioned by discs.These vertebrae are divided by region: neck (cervical spine), mid-back (thoracic spine), and low back (lumbar spine). At the lower end of your spine, you also have the sacrum and the coccyx, which is commonly called your tailbone. Discs are present between these bones. The disks protect the bones by absorbing the shocks from daily activities like walking, lifting, and twisting. Each disk has two parts—a soft, gelatinous inner portion (nucleus pulposus) and a tough outer ring (annulus fibrosis) . Together, the vertebrae and discs form a tunnel through which the spinal cords and nerve pass.