What does "===" mean?

comparison-operators, identity-operator, operators, php

Solution

$a === $b     (Identical)      

TRUE if `$a` is equal to `$b`, and they are of the same type. (introduced in PHP 4)

PHP Docs

Problem

I've noticed someone using the PHP operator `===` which I can't make sense out of. I've tried it with a function, and it corresponds in crazy ways. What is the definition of this operator? I can't even find it in the declaration of PHP operators.

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