title: Can I just remove data in localStorage by its key?
body: <p>I am learning about HTML5 these days.</p>
  
  <p>Here comes trouble when I want to remove just one of the data in the localStorage.</p>
  
  <p>I know a method called <code>clear()</code> to remove anything, but what can I do if I just remove one of the data by its key?</p>