A Stem Cell Donor is a person who provides stem cells, which are special cells that can develop into different types of cells in the body. These cells are often used in medical treatments for conditions like leukemia and other blood disorders. Donors can be found through registries, and they may be asked to donate stem cells from their blood or bone marrow. The process of donating stem cells is generally safe and can be done in two ways: through a blood donation or a minor surgical procedure to collect bone marrow. Donors play a crucial role in helping patients who need transplants to recover and improve their health.