AJAX Fluency

AJAX - Requesting a JSON file

AJAX stands for Asynchronous JavaScript And XML. It's used to request data from a server and recieve that data and send data to a server without reloading the page. It uses the XMLHttpRequest object to get or send HTTP responses within a page.

First we create an instance, then define a callback function to an event listener "onreadystatechange." When something changes after making a connection to the server with the xhttp.open method, the data is returned in JSON format.

In this example, I use 'GET' to make a call to an URL (www.api.bitcointrade.com) and the content is returned as a JSON string.