<?php

  $a = 4;
  $b = 4.0;
  $c = "4";

  echo '$a == $b: ';
  var_dump($a == $b);
  echo "\n";

  echo '$b == $c: ';
  var_dump($b == $c);
  echo "\n";

  echo '$a == $c: ';
  var_dump($a == $c);
  echo "\n";

  echo '$a === $b: ';
  var_dump($a === $b);
  echo "\n";

  echo '$b === $c: ';
  var_dump($b === $c);
  echo "\n";

  echo '$a === $c: ';
  var_dump($a === $c);
  echo "\n";

?>

$a == $b: bool(true)

$b == $c: bool(true)

$a == $c: bool(true)

$a === $b: bool(false)

$b === $c: bool(false)

$a === $c: bool(false)