Why Does My JavaScript `alert()` Show '[object Object]'?

Unraveling the Enigma of "[object Object]"

Encountering "[object Object]" in an alert can be perplexing for those attempting to display the value returned by a function. To clarify this apparent mystery, we delve into the depths of JavaScript's object mechanism.

The default serialization of an object results in the "[object Object]" notation. Однако this is not the entire story, as JavaScript differentiates between various types of objects.

Distinctive Object Types in JavaScript:

• Function objects: Serialized as "[object Function]"
• Array objects: Serialized as "[object Array]"
• RegExp objects: Serialized as "[object RegExp]"
• Date objects: Serialized as "[object Date]"
• Object objects: Serialized as "[object Object]"

The presence of the "Object" (with a capital "O") in the default serialization stems from the constructor function for this type of object. In contrast, the generic term "object" (with a lowercase "o") refers to the inherent structure of a data entity.

Typically, when referencing "objects" in JavaScript, we imply "Object objects" rather than other object variants. This clarification should shed light on the seemingly cryptic "[object Object]" notation.

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