A/B testing is a method used to compare two versions of something to see which one performs better. For example, a website might show half its visitors version A of a webpage and the other half version B. By analyzing how users interact with each version, businesses can determine which design or content leads to more clicks, sign-ups, or sales. This technique is widely used in marketing and product development. Companies like Google and Amazon rely on A/B testing to optimize their user experience. By making data-driven decisions, they can improve their services and better meet the needs of their customers.