A Simple Guide to Idempotency

Have you ever been on a checkout page, clicked the "Pay Now" button, and nothing happened?. Your first instinct might be to click it again, or maybe three more times to be sure it went through. In a poorly designed system, those extra clicks could mean you get charged four times for the same pair of shoes. In a well-designed system, no matter how many times you smash that button, you are only charged once. This reliability is thanks to a concept called Idempotency . What exactly is Idempotency? Idempotency is a safety guarantee that ensures making the same request multiple times has the exact same result as making it just once. Think of it like an elevator button, If you enter an elevator and press the "5" button, the elevator knows to go to the fifth floor. If you get impatient and press the "5" button ten more times, the elevator doesn't go to the fifth floor ten times; it simply stays committed to the original destination. The outcome remains the same regardless of the extra presses