Some of my first PHP instructions:

*) Redirect ala cfhtttp:
header("Location: http://www.sitebuddy.com/");

*) Print and halt execution, basic troubleshooting technic...
print "Value of aVariable: ($aVariable)";
exit("Value of filename: ($filename)");

print() function ref: http://us2.php.net/manual/en/function.print.php
exit() function ref: http://us2.php.net/manual/en/function.exit.php

PHP, Javascript and VBScript Language Summary:
http://phplens.com/phpeverywhere/node/view/30