A simple introduction to ajax

I have been watching AJAX videos these days. After watching the videos, I found that AJAX is not that simple. Some knowledge points are a bit difficult to understand, and many of them are unfamiliar concepts. Therefore, I wanted to write a blog to briefly understand what I know about AJAX. A further understanding, and then continue watching the video, and completing the examples will be much better. Okay, without further ado, let’s look at the content.
AJAX refers to "Asynchronous JavaScript And XML" (Asynchronous JavaScript And XML). AJAX is a programming model popularized by Google in 2005. It is a web development technology for creating interactive web applications. Web application interactions such as Flickr, Backpack and Google have made a qualitative leap in this regard. The term comes from describing the transition from web-based applications to data-based applications. In data-based applications, the data required by the user, such as contact lists, can be obtained from a server independent of the actual web page, and can be dynamically written into the web page, coloring the slow web application experience and making it look like a desktop application. . AJAX is not a new programming language, but a new way of using existing standards. With AJAX, you can create better, faster, and more user-friendly Web applications. AJAX is based on JavaScript and HTTP requests.
The core of AJAX is the JavaScript object XmlHttpRequest. This object was first introduced in Internet Explorer 5 and is a technology that supports asynchronous requests. In short, XmlHttpRequest allows you to use JavaScript to make requests to the server and handle the response without blocking the user. AJAX allows web pages to be updated asynchronously by exchanging a small amount of data with the server in the background.