Mitosis is a process of cell division that results in two genetically identical daughter cells from a single parent cell. It occurs in somatic cells, which are all the body cells except for the germ cells (sperms and eggs).
Somatic cells undergo mitosis for growth, tissue repair, and asexual reproduction in some organisms. For instance, when you cut your skin, mitosis rapidly produces new cells to heal the wound.
On the other hand, germ cells undergo a different type of cell division called meiosis, which results in gametes with half the number of chromosomes necessary for sexual reproduction.
In summary, mitosis primarily occurs in somatic cells, and while it is crucial for growth and maintenance, it does not occur in germ cells, which instead undergo meiosis.