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javascript - typeof typeof x returns string and not object since type of null is object

I am new to js, trying to learn js, can you guys tell me why typeof typeof x returns string, providing code snippet below, if i understand this simple concept it will help me more:

var x=null;
console.log(typeof typeof x);
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typeof x returns a string representation of the type of x. So, naturally, typeof typeof x is string.

From MDN:

The typeof operator returns a string indicating the type of the unevaluated operand.


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