what is xmlhttprequest method must be used to send a post request code example

Example: What XMLHttpRequest method must be used to send a POST request to the server?

var url = "get_data.php";
var params = "lorem=ipsum&name=binny";
http.open("POST", url, true);

//Send the proper header information along with the request
http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
http.setRequestHeader("Content-length", params.length);
http.setRequestHeader("Connection", "close");

http.onreadystatechange = function() {//Call a function when the state changes.
	if(http.readyState == 4 && http.status == 200) {
		alert(http.responseText);
	}
}
http.send(params);