Tryit Editor v1.8

Source Code:

<!DOCTYPE html>
<html>
<head>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js">
</script>
<script>
$(document).ready(function(){
  $("#btn1").click(function(){
    $("div").data("greeting", "Hello World");
    alert("Greeting is: " + $("div").data("greeting"));
  });
  $("#btn2").click(function(){
    $("div").removeData("greeting");
    alert("Greeting is: " + $("div").data("greeting"));
  });
});
</script>
</head>
<body>

<button id="btn1">Attach data to div element</button><br>
<button id="btn2">Remove data attached to div element</button>
<div></div>

</body>
</html>

Result:

W3Schools.com - Try it yourself

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