Behavior-Driven Development (BDD) is a software development approach that extends Test-Driven Development (TDD) by emphasizing collaboration between developers, QA, and non-technical stakeholders. BDD encourages the use of simple, descriptive language to formulate software requirements in a way everyone can understand. This helps ensure that the software developed meets the expectations of all parties involved. By focusing on the behaviors of an application from the perspective of users, it allows teams to produce clear specifications and fosters better communication throughout the development process.