disc - This is the soft tissue found between the bones of the spinal column, (i.e., the vertebrae). They help cushion the spine from everyday stress (i.e., running, walking, jumping, etc.). Through improper posture (i.e., bending forward at the waist and twisting), discs can wear out (degenerate). This can lead to the condition known commonly by the laymen, as a "slipped disc", or a disc herniation.