A deceased donor is an individual who has passed away and has consented to donate their organs and tissues for transplantation. This process typically occurs after the donor has been declared brain dead or has suffered cardiac death, ensuring that their organs are still viable for recipients in need. The organs from deceased donors can include the heart, kidneys, liver, lungs, pancreas, and intestines. These donations are crucial for patients suffering from organ failure, as they can significantly improve or save lives. Organizations like the United Network for Organ Sharing (UNOS) manage the allocation of these organs to ensure fairness and efficiency in the transplant process.