A "Use Case" is a description of how a user interacts with a system to achieve a specific goal. It outlines the steps taken by the user, known as the actor, and the system's responses. Use cases help in understanding user requirements and guide the development process. In software development, use cases are essential for identifying features and functionalities. They provide a clear framework for developers and stakeholders, ensuring that the final product meets user needs. By focusing on real-world scenarios, use cases facilitate better communication among team members and improve project outcomes.