Data Types are made on the basis of how data are stored and how it is accessed.

1. Primitive Data Types: | (Call By Value ⇒ Changes are made in Copy)

   • String: Represents a sequence of characters (e.g., 'Hello', "World").
   • Number: Represents numeric values (e.g., 42, 3.14).
   • BigInt: Represents integers with arbitrary precision (e.g., 9007199254740991n).
   • Boolean: Represents true or false.
   • Undefined: Represents a variable that has not been assigned a value.
   • Null: Represents the intentional absence of any object value.
   • Symbol: Represents a unique and immutable value often used for object property keys.

   Total 7 Data Types in Primitive Classification.

2. Non-Primitive (Reference) Data Type: | (Call By Reference ⇒ Changes in the Original Values)

   • Object: Represents collections of key-value pairs, such as arrays, functions, and plain objects (e.g., { name: "John" }).
   • Array
   • Functions

1. Primitive Data Types

These are the most basic data types in JavaScript.

Characteristics:

• Immutable (cannot be changed once created).
• Stored directly in memory (stack).
• Compared by value.

Types:

1. Number: Represents numerical values, both integers and floating-point numbers.

   let age = 25;
   let price = 99.99;
   
   

2. String: Represents textual data, enclosed in single (') or double (") quotes or backticks (`).

   let name = "John";
   
   

3. Boolean: Represents true or false.

   let isLoggedIn = true;
   
   

4. Undefined: A variable that has been declared but not assigned a value.

   let x;
   console.log(x); // undefined
   
   

5. Null: Represents an explicitly empty or unknown value.

   let data = null;
   
   

6. Symbol: Introduced in ES6, used to create unique identifiers.

   let sym = Symbol("id");
   
   

7. BigInt: For numbers larger than 2^53 - 1 (safe integer limit).

   let bigNumber = 123456789012345678901234567890n;
   
   

2. Non-Primitive Data Types