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Rakshambika
Rakshambika

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Data Types in JavaScript

What is Datatype?

  • Datatype is used to tell us that what kind of data is stored inside a variable.

Example:

let name = "Raksha";  // String
let age = 21;         // Number
let isStudent = true; // Boolean
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  • There are two types of Datatypes:

           1. Primitive Datatype
           2. Non-Primitive Datatype
    

Primitive Datatype:

  • Primitive Datatypes are used to store a single value.
  • Primitive Datatypes in JavaScript are immutable in nature.
  • Immutable means their value can't be changed after creation.

Types of Primitive Datatypes:

        1. Number
        2. String
        3. BigInt
        4. Boolean
        5. Undefined
        6. Null
        7. Symbol
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Number:

  • Number datatype is used to store the numeric values including both integer and decimals values.

Example:

let age = 21;
let marks = 85.5;
let temperature = -10;

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Output:

console.log(typeof age);         // number
console.log(typeof marks);       // number
console.log(typeof temperature); // number

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String:

  • string datatype is used to store sequence of characters as well as single characters.

Example:

let name="Raksha";
let grade="O";
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Output:

console.log(typeof name);  // string
console.log(typeof grade); // string
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Boolean:

  • boolean datatype is used to store true or false values.

Example:

let isStudent = true;
let isLoggedIn = false;
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Output:

console.log(typeof isStudent); // boolean
console.log(typeof isLoggedIn); // boolean
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BigInt:

  • bigint is used to store very large integer values. It is created by adding n at the end of an integer.

Example:

int largeNumber=123456789905322324456667864433n;
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Output:

console.log(typeof largeNumber); // bigint
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Undefined:

  • undefined datatype is used represents a variable that has been declared but has not been assigned a value.

Example:

let animal;
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Output:

console.log(typeof animal); // undefined
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Null:

  • null datatype is used to intentionally make the variable as empty.

Example:

let user = null;

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Output:

console.log(user); // null
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Top comments (2)

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berlin_07_87ce4b42d1d5c02 profile image
Berlin_07

Great work Rakshambika

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raksha_murugesan profile image
Rakshambika

Thank You