title: jQuery get all divs which do not have class attribute
body: <p>get all divs which has class attribute</p>
  
  <pre><code>$('div[class]')
  </code></pre>
  
  <p>get all divs which do not have class attribute</p>
  
  <pre><code>$('div[class!=""]')
  </code></pre>
  
  <p>This code works but I don't understand why it works. If the above code works then the code for all divs with class attribute should be</p>
  
  <pre><code>$('div[class=""]') 
  </code></pre>
  
  <p>which does not yield any result.</p>