EMT is short for EMT-Basic, or EMT-B, and refers to a technician who has less training than an EMT-Paramedic, often simply referred to as a paramedic. EMTs and Paramedics both provide care for patients in the ambulance before they arrive at the hospital.
Comparison chart
Training
In order to become an EMT, an individual must receive 120 to 150 hours of training in emergency care and basic life support.
In order to become a paramedic, an individual must take the course required for an EMT, and then build upon this information with 1200 – 1800 hours of additional training in a two-year degree course. Not all EMTs choose to continue training to become paramedics.
Responsibilities
An EMT provides basic life support to patients in the ambulance, as well as driving the ambulance itself. If a paramedic is present, they assume a support role. They can use oxygen, glucose, asthma inhalers and epinephrine auto-injectors to support breathing, but most states do not allow them to give shots (with a few exceptions) or start intravenous lifelines.
A paramedic is responsible for providing both basic and advanced life support, as well as giving supportive care to patients and maintaining them after resuscitation. They are trained in the use of between 30 and 40 medications.
The presence of EMTs and paramedics in ambulances varies. An ambulance with only EMTs is considered a “basic life support unit,” while an ambulance with paramedics is considered an “advanced life support unit.” Some states allow ambulance teams to contain both EMTs and paramedics.
Salary
According to Salary.com, the median salary of an EMT-B is around $30,247 whereas for a Paramedic it is $38,347.

Video explaining the differences
In this video, EMS Corporate Director explains the differences between various response vehicles and the role EMT and Paramedics play during an emergency situation:
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