Yesod is a web framework for the Haskell programming language, designed to facilitate the development of web applications. It emphasizes type safety and modularity, allowing developers to create robust and maintainable code. Yesod uses a unique approach to routing and templating, making it easier to manage web application structure. The framework is built on top of Wai, a web application interface for Haskell, and leverages Persistent for database interactions. Yesod supports various features like authentication, form handling, and internationalization, making it a comprehensive choice for developers looking to build scalable web applications in Haskell.