The mechanical function of the spine is two-fold: it must provide structural support for the body, and allow us to move freely in three dimensions (bending over and rotating as necessary); the neurological function of the spine, of course, is to innervate (or provide a nerve supply to) the rest of the body.

In order to understand how both of these functions are achieved, we first need to understand the structure of the individual vertebrae, and how they come together to form the column itself.