Code:
<script>
$.getJSON("https://www.gamerholic.com/gamerholic_api/db_api_v1.php? user=1&key=6054abe3517a4da6db255e7fa27f4ba001083311&gameid=1&action=authenticate", function () {
alert("aaa");
});
</script>
The above code is
jQuery and so requires the jQuery library to be attached to the page. The space before the word user also needs to be removed.