A defibrillator is a life-saving medical device designed to deliver an electric shock to the heart during cardiac arrest. One specific type of defibrillator is the Automated External Defibrillator (AED), which is designed for easy use by non-medical professionals in emergency situations. This content will explore the importance of defibrillators, the functionality of AEDs, and their role in saving lives. Cardiac arrest occurs when the heart suddenly stops beating, leading to a lack of blood flow to the brain and other vital organs. The shock interrupts the abnormal heart rhythm, allowing the heart to reestablish a normal, coordinated rhythm. Increasing awareness, accessibility, and education regarding AED usage can save more lives in the critical moments following cardiac arrest. defibrillators, particularly AEDs, are vital tools in the effort to increase survival rates during cardiac emergencies. Their simplicity, accessibility, and effectiveness make them indispensable in both public and private settings.