Line 11: el.innerHTML = x.responseText;
}
}
Line 12: x.open("GET", args[1], true);
Line 13: x.send(null);
}
Line 14: break;
Line 15: case "start_up":
Line 16: ajaxManager('load_page', 'basic.xml', 'contentLYR');
Line 17: break;
}
}

As you may have noticed, I have numbered the JavaScript on a line by line basis. The best way to learn JavaScript is line by line, consequently it will be employed through this tutorial when apt.