There are 2 types of stem cells Adult Stem Cell and Embryonic Stem Cells:

 An adult stem cell is thought to be an undifferentiated cell, found among differentiated cells in a tissue or organ.  The adult stem cell can divide itself and heal the tissues and organs. The main role of adult stem cells in a living organism are to preserve and repair the tissue in which they are found, but the catch is that they are limited and will stop to divide over time.

Embryonic stem cells are found in the early developing embryo and they help form a baby in in its early stages and they are unlimited, they are the perfected versions of an adult stem cells.

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