What does null mean in js?

There are two primitive types in JavaScript: Null and Undefined. These two types often cause confusion among JavaScript developers. What do Null and Undefined mean respectively?

#The Null type has only one value, null. Null is used to represent an object that does not yet exist. It is often used to indicate that a function attempts to return a non-existent object.

The Undefined type also has only one value, which is undefined. When a declared variable has not been initialized, the variable's default value is undefined.

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