use of explode function and file_get_contents functions

how can we hack the contents of others sites?
how can we links others site with ours?
how can we show others contents in our sites?
<?php
/*$data='<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td>one</td>
</tr>
<tr>
<td>Two</td>
</tr>
<tr>
<td>Three</td>
</tr>
<tr>
<td>Four</td>
</tr>
<tr>
<td>Five</td>
</tr>
</table>';*/


$test=file_get_contents("http://www.cybernepal.com.np");

echo $test;



//$break=explode("</tr>",$data);
//print_r($break);

?>