how load content as pop-up using ajax

If you want to load PHP file through AJAX use the below code.

function sendAJAX(){
    $('#container').load(
    "stuff.php",  // url
    { // json object of data to pass to the page
        stuff: "all your stuff goes in here...",
        moreStuff:  "even more stuff"
    });
    console.log('sendAJAX'); 
};

Let me know, In case of any doubts.