"EMS" stands for Emergency Medical Services which today is a critical component of the nation's emergency, trauma care, and public health systems. EMS is part of the initial stages of the continuum of emergency care which includes emergency calls to 9-1-1; the dispatching of emergency personnel to the scene of an illness or trauma; providing on-scene care; providing care in transit; and transferring patients to definitive care either by ambulance or air medical service.

These functions of the EMS system are represented by each of the bars in the "Star of Life" symbol which was designed by the National Highway Traffic Safety Administration and is now used and recognized world-wide.