The fluid that surrounds the brain and spinal cord is called cerebrospinal fluid (CSF). This clear, colorless liquid serves multiple essential functions, including cushioning the brain and spinal cord, providing buoyancy, and protecting against injury. CSF also helps to regulate intracranial pressure and facilitates the exchange of nutrients and waste products between the brain and the bloodstream. Produced mainly in the choroid plexus of the brain's ventricles, CSF circulates through the ventricles and the subarachnoid space surrounding the brain and spinal cord. Its importance is highlighted by its role in maintaining a stable environment for the central nervous system.