At a high level an AJAX request consists of the URL you a making a request to, and then corresponding settings to handle the response. Below are a few of the more popular callbacks that make up the settings:
Example 1: makes a request to ‘index.html’ and then inserts the response into the item in the DOM that has a class called “hello-world”
Example 5 demonstrates some of the callback settings. In this AJAX request, if the response is not successfully made it will stop the request after 3 seconds (3000 milliseconds). It also demonstrates common code for adding a loading animation while the request is being made.