Application of $. Ajax of method in jQuery

 
$.ajax({ 
type:"POST", 
url:"../page/user.action?userId=" + userNo, 
dataType:"json", 
data:{ 
"userId":userNo, 
"userName":username 
}, 
success:function(data){ 
console.info(data.items); 
console.dir(data.items.length); 
} 
});