Resuscitation is a medical procedure that attempts to revive someone who has stopped breathing or whose heart has stopped beating. The goal of resuscitation is to restore normal blood flow and oxygen supply to the body, in order to prevent brain damage or death. Resuscitation can involve various techniques such as cardiopulmonary resuscitation (CPR), defibrillation, or medications to regulate heart rhythm. The term "resuscitate" refers specifically to the act of reviving someone who has experienced a life-threatening event, and may be performed by medical professionals or laypersons trained in first aid techniques.