What Is The Difference Between Ventricular Ectopy And Supraventricular Ectopy?

Background: I m 55, not overweight, exercise regularly, no smoking nor drinking, low blood pressure, no previous family history. Regardless of that I recently had a heart attack. Subsequently had two Holter tests. The doctor says the amount of ventricular ectopy and supraventricular ectiopy is normal. 3 questions. 1. in layman s terms what is the difference between ventricular ectopy and supraventricular ectopy? 2. what is normal amount/percent of ventricular ectopy is normal (i had 43 the first 24 test and only 4 the second test) 3. same question for supraventricular ectopy (i had 4 in the first 24 test and 21 in the second 24 hr test). Thank you