Triage is the process of sorting patients based on the urgency of their condition to provide the right care to the right patient at the right time. It involves initially assessing patients at arrival to identify those needing immediate care, determine the appropriate treatment area, and avoid congestion. The goals are to treat the most severely injured first while maximizing survival in a mass casualty event. Triage categories range from resuscitation to non-urgent to ensure critical patients receive rapid medical attention. Reassessment is important as a patient's condition may deteriorate while waiting.