Variable Scope in PHP

Scope defines where a variable can be used.

Local scope

function test() {
  $x = 10;
  echo $x;
}

Global scope

$x = 5;

function show() {
  global $x;
  echo $x;
}

Static variables

function counter() {
  static $count = 0;
  $count++;
  echo $count;
}

counter(); // 1
counter(); // 2

Next: Superglobals like $_GET and $_POST.