<?php print 'hello world ! '; echo '<br/>'; ?> <?php $number="16"; $number2="12"; //use dot to link str echo $number.$number2; ?> <?php echo '<br/>'; echo strlen('Hello World !'); echo '<br/>'; echo strpos('Hello World !','o') ?> <?php echo '<br/>'; $d=date("D"); if($d=="Fri") { echo 'Hello<br/>'; echo 'Have a nice day!'; } else { echo 'Today is '.$d.'<br/>'; } ?> <?php switch($d) { case 'Wed': echo 'Have a nice day !'; break; default: echo 'Today is '.$d; } ?>