What is the purpose of "global $current_user;"?

By the way, here are some nifty examples to run. Here's one version where two exactly the same variables are used, one is declared outside the function, and one inside. Check out the values:

<?php
$a = 5;

function maybeAChange () {
  $a = "friend";
  return "$a inside the function<br>";
}

echo maybeAChange();
echo "$a outside the function";
?>

And then here is the same example, except where the $a variable is imported from the global scope:

<?php
$a = 5;

function maybeAChange () {
  global $a;
  $a = "friend";
  return "$a inside the function<br>";
}

echo maybeAChange();
echo "$a outside the function";
?>

Why does the teacher have to write the current user variable outside the function? Why not write it inside the function?

No problem, man! Paying it forward is what it's all about, Mike. By the way, it looks like you did select me as best answer, but then it is gone lol. It is cool if you want to wait, but if I answered your question, I do appreciate being selected as best answer.

It's no biggie to me at all, and I'm just glad I could help. Happy Coding!