title: stringWithFormat vs. initWithFormat on NSString
body: <p>I am wondering what differences such as disadvantages and/or advantages there are to declaring an NSString this way:</p>
  
  <pre><code>NSString *noInit = [NSString stringWithFormat:@"lolcatz %d", i];
  </code></pre>
  
  <p>as opposed to:</p>
  
  <pre><code>NSString *withInit = [[NSString alloc] initWithFormat:@"Hai %d", i];
  </code></pre>
  
  <p>What was the motivation of putting <code>stringWithFormat</code> instead of just having the <code>initWithFormat</code> way of initializing the string?</p>