Neural stem cells (NSCs) are self-renewing, multipotent cells that firstly generate the radial glial progenitor cells that generate the neurons and glia of the nervous system of all animals during embryonic development Some neural progenitor stem cells persist in highly restricted regions in the adult vertebrate brain and continue to produce neurons throughout life. Stem cells are characterized by their capacity to differentiate into multiple cell types. They undergo symmetric or asymmetric cell division into two daughter cells. In symmetric cell division, both daughter cells are also stem cells. In asymmetric division, a stem cell produces one stem cell and one specialized cell. NSCs primarily differentiate into neurons, astrocytes, and oligodendrocytes. There are two basic types of stem cell: adult stem cells, which are limited in their ability to differentiate, and embryonic stem cells (ESCs), which are pluripotent and have the capability of differentiating into any cell type. Neural stem cells are more specialized than ESCs because they only generate radial glial cells that give rise to the neurons and to glia of the central nervous system (CNS). During the embryonic development of vertebrates, NSCs transition into radial glial cells (RGCs) also known as radial glial progenitor cells, (RGPs) and reside in a transient zone called the ventricular zone (VZ). Neurons are generated in large numbers by (RGPs) during a specific period of embryonic development through the process of neurogenesis, and continue to be generated in adult life in restricted regions of the adult brain. Adult NSCs differentiate into new neurons within the adult subventricular zone (SVZ), a remnant of the embryonic germinal neuroepithelium, as well as the dentate gyrus of the hippocampus.