What types of defibrillators are there?

Internal & external: Implantable (internal) defibrillators remain in the body, whereas external defibrillators are the boxes with paddles that you see on tv shows. They both shock the heart out of life-threatening cardiac arrest rhythm if need be. There are automated external units that lay people can use; you put paddles on person's chest and the machine determines the rhythm and speaks commands to give a shock.

Defibrillators: We have implantable defibrillators which are combination pacemakers and defibrillators. Within this group are subtypes. There are three types of external defibrillator. One is a vest worn on the outside that functions like the internal; this isn't for long term use. Then there is the AED automatic external defibrillator for lay people to use and the external defibrillators for medical staff.