title: php Timestamp working logic
body: <p>what is exactly happing when creating a Unix Timestamp from a given date.</p>
  
  <p>I want the step by step method to create timestamp. (not using php built in functions).</p>
  
  <p><strong>EDIT:</strong> What is the specialty of this date :) <strong>January 1st 1970 00:00 h UTC</strong> </p>