title: Is there any difference in strtotime +day or +days?
body: <p>Was googling this, but couldn't find the answer. Was wondering, if there is a difference in these two scripts?</p>
  
  <p>+3 <strong>day</strong>:</p>
  
  <pre><code>echo date( 'd.m.Y H:i:s', strtotime( '+3 day' ) );
  </code></pre>
  
  <p>+3 <strong>days</strong>:</p>
  
  <pre><code>echo date( 'd.m.Y H:i:s', strtotime( '+3 days' ) );
  </code></pre>
  
  <p>The output is exactly the same.</p>
  
  <p>So is that implemented to make sure people get less errors or what?<br />
  And witch one should be preferred to use?</p>