Here is a 1-paragraph summary of the text: This tutorial demonstrates how to create a secured RESTful API with CodeIgniter and JSON Web Tokens. The API allows users to register, authenticate, add, edit, and delete clients. A JWT authentication filter is implemented to secure the API endpoints, requiring authenticated users to provide a valid token in the Authorization header. The API uses a local database instance and follows best practices for security, validation, and error handling, making it suitable for production use.