Triage is the process of prioritizing patients for treatment based on the severity and urgency of their conditions, ensuring those with the most critical needs receive immediate attention while those with less urgent conditions wait appropriately. Emergency departments use triage systems where trained nurses assess arriving patients and assign priority levels. The Canadian Triage and Acuity Scale (CTAS) provides standardized categories from Level 1 (resuscitation needed) to Level 5 (non-urgent). Triage ensures efficient resource use when demand exceeds immediate capacity. During mass casualty events or pandemic surges, triage becomes especially critical. Understanding triage helps patients understand why some people seen later may receive treatment sooner—it reflects medical priority, not arrival time.