Basic XHR example

HTML

<input type="button" id="basicXHRButton" value="Try It">

JavaScript

document.getElementById("basicXHRButton").addEventListener("click", function() {
        // Loading the jQuery code
        request = new XMLHttpRequest();
        request.open("GET", "http://api.geonames.org/countryInfo?lang=it&country=DE&username=demo&style=full", true);
        request.send(null);

        request.onload  = function() {
        debugger;
            if(request.readyState === 4) { // What does this even mean?
                if(request.status === 200) {
                    console.log(request.responseText);
                    
                    var response=request.responseText;
                    var xmlText=response.replace('GM',"and");
                    
                    var parser = new DOMParser();
xmlDoc = parser.parseFromString(xmlText,"text/xml");
                    
                   console.log(xmlText)
                }
            }
        }
    });