Difference Between Primitives and Non-Primitives in JavaScript

What are Primitives and Non-Primitives?

In JavaScript all data is divided into two types:

Primitive Types — values that are not objects and have immutable value.
Non-Primitive Types (Reference Types) — objects that are stored and passed by reference, can be mutable.

Primitives are basic types built into the language.

Type	Example	Features
`string`	`"Hello"`	Text string
`number`	`42`, `3.14`	Any number (integer and floating point)
`boolean`	`true`, `false`	True or false
`null`	`null`	Intentional absence of value
`undefined`	`undefined`	Value wasn't assigned
`bigint`	`900719925...n`	Large numbers
`symbol`	`Symbol('id')`	Unique identifiers

Summary:

Primitives are simple, immutable values passed by value. Non-primitives are objects passed by reference.

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