Ajax is a technology used in web development that allows web pages to update content without needing to reload the entire page. This means that when you interact with a website, like clicking a button or submitting a form, only the necessary parts of the page change. This creates a smoother and faster user experience, making websites feel more responsive. One common use of Ajax is in online forms, where users can see instant feedback without waiting for a new page to load. For example, when you search for something on a website, Ajax can help display results as you type, making it easier to find what you need quickly.