Glia are non-neuronal cells that are found in the peripheral and central nervous system. Glial cells have various kinds of shapes, types, sizes, each with their specialized functions. In the central nervous system, there are 3 types of neuroglia: microglial cells, astrocytes, and oligodendrocytes. In the peripheral nervous system, the 3 main types of neuroglia are Schawn cells, enteric glia, and satellite cells.