PHP Boolean true/false issue in 'if' statement [duplicate]

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• How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ? 17 answers

The following code

$status = true;

if($status == 'all') {
  echo "Hello!";
} else {
  echo "Bye!";
}

outputs "Hello" when $status = true, but "Bye" when $status = false. Why is that the case?