Stem cells are unspecialized cells that can differentiate into specialized cells and aid in repairing the body. There are four main types of stem cells: embryonic, adult, induced pluripotent, and mesenchymal, each with unique capabilities and applications in medicine. Stem cell therapy can utilize various methods of administration, and the Plexus Neuro and Stem Cell Research Centre in India specializes in autologous mesenchymal stem cell treatments.