What is: Ajax

Although Ajax can refer to a brand of cleaning powder or a mythological hero from ancient Greece, in WordPress, Ajax (sometimes spelled AJAX to differentiate it) is a special type of programming script.

Ajax stands for “Asynchronous JavaScript and XML” and refers to client-side scripts that were first codified in 2006. Ajax’s main function is for a website to exchange information with a server without having to reload a given website. The term “asynchronous” refers to the fact that information can be exchanged independently of other actions, in this case, reloading the website.

If you’re only interested in administering a WordPress website, then you won’t have to worry about what Ajax is or what it does. For developers, however, Ajax is essential for writing scripts, particularly for web applications.

Note: Despite the term XML being included in Ajax’s name, you don’t necessarily need to use XML. Many modern websites prefer to use JSON instead because it is a native functionality of JavaScript.

Ajax is never used as a stand-alone script or technology. It is almost always integrated with the HTML, CSS, JavaScript, and other core components of a website.

You can see Ajax in action in WordPress when creating a new post. If you decide to create a new category and use it with that post, you can do so without having to reload the entire page. The data that is being exchanged in order to make this update happen is powered by Ajax.

Ajax can also be added to plugins. For much more information on this and how to code Ajax, visit the WordPress website.