The ventricular system is a network of interconnected cavities within the brain that produces and contains cerebrospinal fluid (CSF). This fluid cushions the brain, provides nutrients, and removes waste. The system consists of four main ventricles: the two lateral ventricles, the third ventricle, and the fourth ventricle. The lateral ventricles are located in each hemisphere of the brain, while the third ventricle is situated in the center, connecting to the fourth ventricle through a narrow channel called the cerebral aqueduct. The fourth ventricle is located between the brainstem and the cerebellum, allowing CSF to flow into the surrounding space around the brain and spinal cord.