Glial cells, also known as neuroglia or simply glia, are non-neuronal cells in the brain and nervous system. They play a crucial role in supporting and maintaining the proper functioning of neurons within the central and peripheral nervous systems. Glial cells provide structural and metabolic support to neurons, as well as help in maintaining homeostasis, forming myelin sheaths that insulate nerve fibers, and participating in immune responses. There are several types of glial cells, including astrocytes, oligodendrocytes, microglia, and ependymal cells, each with specific functions within the nervous system.