1. Neurons: These are the primary functional units of the nervous system. They are responsible for transmitting electrical signals throughout the body, enabling communication between different parts of the nervous system. Neurons have a unique structure with a cell body, dendrites, and an axon, which allows for the rapid transmission of information.

2. Glial Cells: These are the supporting cells of the nervous system. They provide structural support, insulation, and nourishment to neurons. Glial cells also play a crucial role in maintaining the health and function of the nervous system by removing waste products and protecting neurons from damage. There are several types of glial cells, including astrocytes, oligodendrocytes, and microglia.