Function

<?php

function add($a,$b)

{

       echo $a+$b;

}

add(2,3);

?>

Outrput:5

<?php

function add($a,$b)

{

       return $a+$b."<br>";

}

$a =add(4,5);

echo $a;

?>

Output:9

Variable Variables:

In function , here we can also use variable variables process. Where we can assign function name in another variable.

For example:-

<?php

function add($a,$b)

{

       return $a+$b."<br>";

}

$fun='add';

echo $fun(5,6);

?>

Output:11

Here ‘add’ function name is assign in ‘$func’.