Not all ambulance vehicles are the kind most people think of when they think of an ambulance, those vehicles are actually emergency medical vehicles. There are also non urgent transport vehicles.
Emergency medical vehicles
Emergency medical vehicles are vans, helicopters, aircrafts (also known as air ambulances), boats and in some cases remade golf carts. These vehicles are equipped with life saving medical equipment and also emergency medical technicians who aide in life saving emergency care until the patient arrives at the hospital.
Patient transport ambulance
Patient transport vehicles are sometimes called an ambulette. They consist mostly of vans and buses. These vehicles are usually not equipped with any life saving equipment and the staff in the patient transport vehicle usually has fewer qualifications than that of an emergency medical technician. These vehicles are not used for emergencies but rather to places like a dialysis center or doctors appointments for those who are highly ill. All in all an ambulette is simply just a transport vehicle, not an ambulance like you would picture, and in most countries is not equipped with flashing lights.
Response units are usually in the form of a fly car. Response units are used to get to patients quickly to administer emergency care to acutely ill patients. Response Unit vehicles have no ability to transport the patient. However will most likely be followed by one or two emergency response vehicles.
A charity ambulance is a special kind of ambulance, usually a bus, provided by a charity. The charity ambulance takes patients who stay long term in the hospital. Terminally ill children and adults away from the hospital to go on trips or vacations.
A bariatric ambulance is a medical transport system for extremely obese and elderly patients and is equipped with the proper tools to transport them.
Some other vehicles used to transport patients are station wagons and hospital ships (also known as floating hospitals).