Cell is the structural and functional unit of life. A living cell is a true representative of life with its own organisation and specialised functions. Scientists have been interested in cell biology since the advent of microscopes in 18th century. Stem cells are defined as clonogenic, unspecialised cells capable of both self renewal for long periods and multilineage differentiation contributing to regenerate specific tissues. They can theoretically divide without limit to replenish other cells as long as the person is still alive. Research on stem cells and their application to treat various diseases is still at a preliminary stage. However, results from animal models are very promising and many researchers believe that it is only a matter of time before the same results can be achieved with human stem cell.