Stem cell is the unspecialized cell which can be transformed to almost any specialized cell.In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues. Generally this approach is used for treatment of diseases and conditions include: Diabetes, Rheumatoid arthritis, Parkinson's disease, Alzheimer's disease, Osteoarthritis, Stroke and traumatic brain injury repair, Learning disability due to congenital disorder, Spinal cord injury repair, Heart infarction , Anti-cancer treatments , Baldness reversal, Replace missing teeth , Repair hearing, Restore vision, Amyotrophic lateral sclerosis, Crohn's disease , Wound healing. Bone marrow transplant is a crude form of stem cell therapy that has been used clinically for many years without controversy. Mostly hematopoietic stem cells (HPC), endothelial stem cells (EPC), bone marrow cells, endothelial progenitor cells, mesenchymal stem cells, brain, fat, liver, muscle, pancreas, umbilical cord are used in alleviating chronic disease conditions. No stem cell therapies other than bone marrow transplant are widely used. In recent approaches stem cells have been found successful in lab grown contracting muscle, hair growth, formation of egg and sperm precursor using embryonic stem cells. Sir Stephen Hawking sees a great hope as this might be able to cure paralysis in the near future, which has been successful in a rat and a successful repairment of spinal cord has been performed. They can also be a great help in cloning as they can generate as well as revive a dead heart.