Neurons are nerve cells, or cells found in the nervous system. These are specialized cells designed to stimulate other cells in the body in order to communicate. Neurons are excitable, which means they function by using electrical stimulation. Through this electrical message, known as an action potential, neurons are able to initiate action in the cells they target.
Neuron come in three functional classes. These classes are derived from the amount of cell extensions that are found on the cell body, or soma. Unipolar neurons are nerve cells that have one extension connected to the soma. These cells are often used in afferent nervous system function, which means that it involves the senses. Bipolar neurons are nerve cells that have two projections and are used in specialized sense detection, such as in smell and sight. Multipolar neurons are nerve cells that have many cell extensions, including dendrites, which are receiving pathways, and typically one axon, which is a delivering pathway. (www.study.com)