The spinal canal is a hollow space within the vertebral column that houses the spinal cord. It runs from the base of the skull down to the lower back, providing protection and support for the nervous system. The canal is formed by the stacked vertebrae, which create a bony tunnel. Inside the spinal canal, the spinal cord is surrounded by protective membranes and cerebrospinal fluid. This fluid cushions the spinal cord and helps to nourish it. The spinal canal also contains nerve roots that branch out to various parts of the body, facilitating communication between the brain and the rest of the nervous system.