Cervical vertebrae: The cervical (neck) vertebrae are the upper 7 vertebrae in the spinal column (the vertebral column). They are designated C1 through C7 from the top down.
C1 is called the atlas. It supports the head and is named for the Greek god Atlas who was condemned to support the earth and its heavens on his shoulders. (Because the god Atlas often adorned maps, a compilation of maps came to be known as an atlas).
C2 is called the axis because the atlas rotates about the odontoid process of C2. The joint between the atlas and axis is a pivot that allows the head to turn.