title: Jquery ajax url in controller action
body: <p>Can some body explain How  actually jquery ajax method url points to a controller action?I mean the machinery behind the technology.For example</p>
  
  <pre><code> $("#Location").autocomplete({
          source: function (request, response) {
              $.ajax({
                  url: '/Vacancy/AutoCompleteLocations',
                  data: request,
                  dataType: "json",
                  type: "GET",
                  minLength: 2,
                  success: function (data) {
                      response($.map(data, function (item) {
                          return { label: item.REF_DESC, value: item.REF_DESC, id: item.REF_ID }
                      }));
                  }
              });
          },
          select: function (event, ui) {
              $("#hdLocationId").val(ui.item.id);
          }
      });
  </code></pre>
  
  <p>I want to know how  url: '/Vacancy/AutoCompleteLocations' points the particular action means the machinery.</p>