title: Javascript how to use the and/or operator with parenthesis
body: <p>I have an object that contains a string <code>HelloWorld</code> in the attribute <code>hello</code>. I want to check for two strings, and if it does not match with either one, then I want to execute certain code.</p>
  
  <pre><code>var item = { hello: "HelloWorld" }
  item.hello !== "HelloWorld" &amp;&amp; item.hello !== "GoodbyeWorld" // false, correct
  </code></pre>
  
  <p>However, I feel this can be optimized and made more readable:</p>
  
  <pre><code>item.hello !== ("GoodbyeWorld" &amp;&amp; "HelloWorld") // false, correct
  item.hello !== ("HelloWorld" &amp;&amp; "GoodbyeWorld") // true   WTF?
  </code></pre>
  
  <p>I expected both checks to be falsy, but surely I'm missing something here. I think I do not have a correct understanding of the AND/OR operator in javascript, or I am using the parenthesis in a wrong manner. Can anyone explain?</p>
  
  <p><a href="http://jsfiddle.net/N97Kv/2/" rel="nofollow">JSFiddle example</a></p>