Answer:
the vertebral column AKA the spine consists of spinal segments (vertebrae) which are joined by:
1. facet joints- which allow the spine to bend forward/back/side, etc.
2. inter-vertebral disks: fluid filled disks which absorb shock and prevent damage to the spinal segments from physical activity
The presence of the discs and the fact that the verterbral column is in an S shape permit flexibility of the vertebral column.