Cucumber is an open-source testing framework designed to support Behavior-Driven Development (BDD). It allows developers and non-technical stakeholders to collaborate on software development by writing tests in a natural language format called Gherkin. These plain-text scenarios describe the expected behavior of the application and are mapped to automated tests, ensuring that the software meets specified requirements. Cucumber supports various programming languages, including Java, Ruby, and JavaScript, making it versatile for different project environments. Its features include scenario outlines, data tables, and hooks for setup and teardown, enabling comprehensive test coverage. By bridging the gap between technical and non-technical team members, Cucumber enhances communication, ensures clarity in requirements, and promotes the development of high-quality, user-centered software.