Transplantation is a medical procedure that involves transferring cells, tissues, or organs from one body to another. This can be done to replace damaged or failing parts of the body, such as a kidney, heart, or liver. The goal is to restore normal function and improve the patient's quality of life. There are two main types of transplantation: autologous, where the donor and recipient are the same person, and allogeneic, where the donor is a different person. Successful transplantation often requires careful matching of donor and recipient to reduce the risk of rejection by the recipient's immune system.