css rule background:url...(img) is applied to <a> object , this always place the imag

[leonidassavvides]

HEAD FIRST AJAX ©2008
css rule background:url
In page 120 : in css rule background:url...(img) is applied to <a> object , this always place the image in place of link <a> ?

#navigation a#beginners {
  background: url('../images/beginnersBtn.png') no-repeat;
}
#navigation a#beginners.active {
  background: url('../images/beginnersBtnActive.png') no-repeat;
}

Ajax
In page 129 : if file in Ajax:...request.open(....file.html....), file.html, does NOT exist on server we get error or NOTHING("") in responseText?

function showSchedule() {
  if (request.readyState == 4) {
    if (request.status == 200) {
      document.getElementById("content").innerHTML = request.responseText;
    }
  }
}

[fg123]

For ajax:

I think it results in a nothing situation because it won't get into the |if status == 200 | part as it returns a 404, not 200.