Usually, a web browser sends requests and immediately receives responses. Every new portion of data requested from the server starts to reload a whole web page. Asynchronous JavaScript and XML (AJAX) is a technology that allows the client-side JavaScript code to request data from a server without the need to reload the current page in the web browser. An important advantage of using AJAX compared to traditional flow of web pages is its ability to bring usability and behavior of desktop applications into a web application. HttpRequest is a client-side XHR request to get data from a URL, formally known as XMLHttpRequest, and has an important role in the AJAX web development technique.
Note
All the requests created within HttpRequest must be in the server from the same origin as the requested resource.
The state of many web applications is inherently volatile. Changes can come from numerous sources, such as other users, external news and data, results of complex calculations...