Change Admin Footer Text

If you need to customize the WordPress administration area, you’ll find this useful.

add_filter('admin_footer_text', 'left_admin_footer_text_output'); //left side
function left_admin_footer_text_output($text) {
    $text = 'How much wood would a woodchuck chuck?';
    return $text;
}

add_filter('update_footer', 'right_admin_footer_text_output', 11); //right side
function right_admin_footer_text_output($text) {
    $text = "That's purely hypothetical.";
    return $text;
}