Selecting elements without specific class in jQuery

If you want to select all same level elements without the ones with specific class in jQuery you can do the following:

$(".tab li[class!=selected]").hover(
    function () {
      $(this).addClass("selected");
    },
    function () {
       $(this).removeClass("selected");
    }
 );

or

 $(".tab li:not(.selected)").hover(
    function () {
      $(this).addClass("selected");
    },
    function () {
       $(this).removeClass("selected");
    }
 );

In the examples above we were assigning class 'selected' to all tabs that were not already selected( elements that not has the class .selected)