title: how to remove existing data from a control in jquery
body: <p>i have a code</p>
  
  <pre><code>&lt;script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"&gt;
  &lt;/script&gt;
  &lt;script&gt;
    $(document).ready(function(){
    $("#btn2").click(function(){
    $("ol").append("&lt;li&gt;Appended item&lt;/li&gt;");
  });
  });
  &lt;/script&gt;
  &lt;body&gt;
   &lt;ol&gt;
  &lt;li&gt;List item 1&lt;/li&gt;
   &lt;/ol&gt;
   &lt;button id="btn2"&gt;Append list item&lt;/button&gt;
  </code></pre>
  
  <p>here each button click "Appended item" is appended in <strong>li</strong> tag.Likewise how can i remove already exist  '<strong>li</strong>' tags and add "Appened item" '<strong>li</strong>' tag</p>