Updated in May 2025.

This course now features Coursera Coach! A smarter way to learn with interactive, real-time conversations that help you test your knowledge, challenge assumptions, and deepen your understanding as you progress through the course. Begin your journey into AJAX with this comprehensive course designed to teach you the principles and practical applications of asynchronous web requests. You will start with an introduction to AJAX, understanding its origins and how it differs from traditional synchronous HTTP requests. Through detailed explanations and examples, you'll learn to write AJAX requests using both the XMLHttpRequest object and the modern Fetch API. The course includes a series of mini-projects to reinforce your learning. In the first mini-project, you'll set up a simple HTML and CSS structure, then fetch text and JSON data from a server using XMLHttpRequest. You will also learn to handle and manipulate the DOM dynamically. The project culminates in making requests to third-party APIs, showcasing the power and flexibility of AJAX in real-world scenarios. Next, you'll advance to a more complex mini-project involving both PHP and Node.js servers. You'll create an input field for users to type in food items, send these items to the server, and display the server's response in the browser. This project will deepen your understanding of URL query parameters, server-side data processing, and AJAX response handling. This course is ideal for web developers, front-end engineers, and anyone interested in enhancing their web development skills. A basic understanding of HTML, CSS, and JavaScript is recommended. No prior knowledge of AJAX or server-side programming is required.