title: How to create an HTML form with pre-filled in "instructions" that clear when a user clicks in the box?
body: <p>I have an HTML form as follow:</p>
  
  <pre><code>   &lt;form method="POST" action="http://"&gt;
   Username: &lt;input type="text" name="username" size="15" /&gt;
   Password: &lt;input type="password" name="password" size="15" /&gt;
  &lt;input type="submit" value="Login" /&gt;
   &lt;/div&gt;
   &lt;/form&gt;
  </code></pre>
  
  <p>I would like functionality such that the text fields have instructions in them that clear when a user clicks in the box so that I can save space and remove the words Username and Password from outside the forms.</p>
  
  <p>How can this be achieved?</p>