XMLHttpRequest is an object of the XMLHTTP component. Through this object, AJAX can only exchange data with the server like a desktop application, without having to refresh the interface every time, and there is no need to hand over the data processing work to the server every time. ; This not only reduces the load on the server, speeds up the response speed, and shortens the user's waiting time.
Starting from IE5.0, developers can use XMLHTTP ActiveX components inside Web pages to extend their own functions. They can directly transmit data to the server or receive data from the server without navigating from the current Web page. , Mozilla1.0 and NetScape7 create the proxy class XMLHttpRequest that inherits XML; for most cases, the XMLHttpRequest object is very similar to the XMLHTTP component, with similar methods and properties, but some properties are different.