Why Does `typeof(null)` Return 'object' in JavaScript?

Question: Why is typeof(null) "object"?

In the context of JavaScript primitives, the question arises as to why the type operator (typeof) returns "object" for the value null. The logic of primitive data types suggests that a primitive value like null should not return "object".

Answer: Historical Inconsistency in JavaScript

The explanation for this inconsistency lies in the early implementation of JavaScript. When JavaScript values were represented by a type tag and a value, null was assigned a type tag of 0, similar to that of objects. This legacy representation became ingrained in JavaScript's behavior despite the existence of a proposed fix that would have changed typeof(null) to "null."

Therefore, although null is considered a primitive data type in JavaScript, the implementation holds a historical artifact that results in typeof(null) returning "object" to preserve backward compatibility with earlier versions of the language.

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