What's the point of function &bar()?

Question

PHP

I'm reading the php documentation section "Passing by reference" I can't understand from just

<?php
function foo(&$var)
{
    $var++; // 6
}
function &bar()
{
    $a = 5;
    return $a; // 5
}
foo(bar()); // кидаем 5 в foo
?>

I can’t understand why we can’t do without & in front of the function, what does it give at all ...

Answer 1

Because it is a link to a "copy" of the object. And it means that it must accept this link (adds 1 to the return).