Usability, also known as user-friendliness, refers to the ease and efficiency with which a person can interact with a product, system, or interface. It encompasses the design, functionality, and overall experience of using a product, with the goal of making it intuitive, efficient, and enjoyable for the user. A product with high usability is one that requires minimal effort to learn and use, and allows the user to accomplish their tasks effectively and efficiently. Usability is a crucial aspect of user experience and plays a significant role in determining the success of a product in the market.