Jinja is a powerful text templating engine for Python, widely used in web development to create dynamic HTML pages. It allows developers to embed logic directly within HTML templates, enabling the use of loops, conditionals, and filters to render content based on data passed from the backend. Jinja promotes code reusability and readability, making it easier to maintain and update web applications. While often associated with Flask, Jinja can also be integrated into Django projects, enhancing the flexibility and efficiency of template rendering. Its features make it an essential tool for building interactive and user-friendly web applications.