The spine, also called the back bone, is designed to provide stability as well as providing a corridor of protection for the delicate spinal cord. The spine is made of bony segments called "vertebra" and fibrous tissue called "inter-vertebral discs". The vertebra and discs form a column from your head to the pelvis giving symmetry and support to the body.
The spine can be divided into 4 parts. The upper section is the cervical region, consisting of 7 small vertebrae that form the neck. The next 12 vertebra form the thoracic region, or mid-back, from which the ribs are hinged. The next 5 lumbar vertebrae are the largest of the mobile vertebra and support 2/3 of the body's weight. The lowest region of the spine is the sacrum and coccyx. The sacrum is a triangular plate made up of 5 fused vertebral segments while the four coccyxes terminate the bony spine.
View an interactive presentation on Spine anatomy.