mouseover

<ul id="test">
  <li>item 1</li>
  <li>item 2</li>
  <li>item 3</li>
</ul>

<script>
  var test = document.getElementById("test");

  // this handler will be executed only once when the cursor moves over the unordered list
  test.addEventListener(
    "mouseenter",
    function (event) {
      // highlight the mouseenter target
      event.target.style.color = "purple";

      // reset the color after a short delay
      setTimeout(function () {
        event.target.style.color = "";
      }, 500);
    },
    false,
  );

  // this handler will be executed every time the cursor is moved over a different list item
  test.addEventListener(
    "mouseover",
    function (event) {
      // highlight the mouseover target
      event.target.style.color = "orange";

      // reset the color after a short delay
      setTimeout(function () {
        event.target.style.color = "";
      }, 500);
    },
    false,
  );
</script>