title: Does NSUserDefaults always do IO when executed?
body: <p>NSUserDefaults is persistent right? If we close application it's still there. So it's IO.</p>
  
  <p>Does that mean everytime we do</p>
  
  <p><code>– setObject:forKey:</code> we do IO?</p>
  
  <p>Does iPhone will read and write to disk everytime we do </p>
  
  <pre class="lang-m prettyprint-override"><code>[[NSUserDefaults standardUserDefaults] setObject:trimmedSearchLocation forKey:SEARCHNEAR];
  </code></pre>
  
  <p>or that sort of thing</p>