17
In that specific piece of code - not very much.
In general however it would be used to return a condition of a validation or code that needs to return either a positive or a negative.
For instance, one would do the following:
public function isValidEmail($email) {
// do work to see if email is valid
if(/* Condition making it true */)
return true;
else
return false;
}
You can read more about return here: http://www.php.net/return
There are few interesting applications of return like returning value from include-d file.