A paramedic is a type of trained emergency personnel that works as part of the first response team in medical emergencies outside of a hospital. They are attached to ambulance services and can provide medical care en route to a hospital that exceeds the general standards of first aid.
Paramedics developed out of ambulance drivers. When ambulances were developed, the only relevant skill was the driver's ability to get to the hospital quickly. The medical attention available in the ambulance was little better than first aid, and ambulance personnel could not deal with many types of emergency situations that were common as a patient was being moved.
As the years progressed, ambulance personnel got medical training well in excess of typical first responders such as firefighters or police officers. Although not as well trained as nurses, paramedics are usually trained to perform defibrillation, to administer some drugs, and to perform minor surgery in addition to typical first aid such as stopping bleeding and administering oxygen. As a result, not only can ambulances travel at a lower rate of speed, the chance that a patient will be Dead On Arrival is now greatly decreased.