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AJAX, when you boil it down, is about manually making "micro" HTTP requests using the XMLHttpRequest (XHR) JavaScript object. It mimics the behavior of the user agent, but instead of using the browser interface, you are using JavaScript to make a programmatic HTTP request (which also handles the response). This technique actually has many names: AJAX, scripting HTTP, XHR, or remote scripting, but personally I prefer the term XHR.