title: Does the img tag's alt attribute require encoding?
body: <p>In html does the text inside the <a href="http://www.w3schools.com/tags/att_img_alt.asp" rel="noreferrer">img tag's alt attribute</a> require encoding/escaping? </p>
  
  <p>Non encoded example:   </p>
  
  <pre><code>&lt;img src="myimg.png" alt="image description" /&gt;
  </code></pre>
  
  <p>Encoded example:  </p>
  
  <pre><code>&lt;img src="myimg.png" alt="image%20description" /&gt;
  </code></pre>