The meninges are three protective membranes that surround the brain and spinal cord, providing support and cushioning. The layers include the dura mater (the outermost layer), the arachnoid mater (the middle layer), and the pia mater (the innermost layer). These membranes help to protect the central nervous system from injury and infection, as well as containing cerebrospinal fluid, which further aids in cushioning and nutrient transport.