Using POST method in AJAX

When we use AJAX concept,frequently we use GET method.There also a way to use POST method in
AJAX.As an example for this we can consider the following example,
var aj=new ActiveXObject("Msxml2.XMLHTTP"); //for IE
var aj=new XMLHttpRequest();//for FireFox and others
aj.onreadystatechange=(state change handling function name);
aj.open("POST","postdata.php",true);
aj.send(name=hiox&id=5555)//here the values name and id are send to server in POST method.