title: Timestamp between Javascript and PHP
body: <p>Javascript:</p>
  
  <p>I have object cell with something date</p>
  
  <pre><code>params.date = cell.getDate();
  params.timestamp = cell.getDate().getTime() / 1000;
  console.log(params);
  </code></pre>
  
  <p><em>Object {date: Thu May 09 2013 00:00:00 GMT+0800 (China Standard Time), timestamp: 1368028800}</em></p>
  
  <p>Then I try to check timestamp in PHP</p>
  
  <pre><code>$date = '1368028800';
  echo date('Y-m-d', $date);
  </code></pre>
  
  <p><em>2013-05-08</em></p>
  
  <p>Difference in one day. Why?</p>