JavaScript Data Types

Data types define what types of data can be stored and manipulated in a program.JavaScript provides different data types to hold different types of values.

  There are two types of data in JavaScript. Which are as follows

1. Primitive data types
2. Non-Primitive data types

We will now discuss in detail the data types of JavaScript.

Primitive data type

  Primitive data types include the following types.

• String
• Number
• Boolean
• Symbol
• BigInt
• Null
• Undefined

Non-Primitive data type

  There is only two type of non-primitive data type which is as follows

• Object
• Array

We will now discuss the types of primitive data types in detail

JavaScript Strings data type

  strings are written with quotes. You can use single or double quotes

  You can learn about strings in the following example.

var india = "Dilhi";
var china = 'Beijing';
document.write( india +" "+ china )             

JavaScript Number data type

  The type of number represents both an integer and a floating point number.

  There are many actions for numbers, e.g. Multiply *, Divide /, Add +, Subtract -, and so on.

var x1 = 10;       // integer
var x2 = 10.5;     // floating-point number
var x3 = 20.1e+5;  // exponential notation    
var x4 = 1.10e-5;  // exponential notation    

JavaScript Boolean data type

  This data type represents logical units. Boolean represents one of two values: true or false.

  The following example illustrates how a boolean works

var x = 5;
var y = 5;
var z = 6;       //output- x == y-true,  y == z-false

JavaScript Symbol data type

  Symbol type is used to create unique identifiers for objects. For the sake of completeness we have to mention it here, but we postpone the details till we know the things.

const company = {
  car1: "maruti",
  car2: "audi",
  car3: "renjo",
  car4: "suzuki"
};

JavaScript BigInt data type

  Bigint is used for integers of arbitrary length

  Bigint type 253-1represents numbers greater than.The letter n is added to the end of a large literal number:

var bigint = 12345678901890n;
document.write(bigint);          //return 12345678901890

JavaScript Null data type

  Null in JavaScript means "nothing". It is believed that which does not exist. You might consider it a bug in JavaScript that typeofnullis an object.

  You can make the value of the object zero or null by turning the object into null.

Understand the null datatype in the following example

var a = "javascript tutorial";
a = null;
document.write(a);       // output: null

JavaScript Undefined data type

  Null in JavaScript means "nothing". It is believed that which does not exist. You might consider it a bug in JavaScript that typeofnullis an object.

  You can make the value of the object zero or null by turning the object into null.

Understand the null datatype in the following example

let car1= "audi";
let car2;
document.write(car1 + "<br>" + car2);   //car2 value is undefined

We will now discuss the types of Non-Primitive data types in detail

JavaScript Object data type

  In JavaScript, an object is an unaltered collection of key-value pairs. Each key-value pair is called a property.

  The key to the property could be a string. And the value of the property can be any value, e.g., string, number, array and even function.

  JavaScript provides you with many ways to create an object. The object is most commonly used to use a literal sign.

  An object can be created with figure brackets {...} with an optional list of properties. Object Properties Name: Value pairs, separated by commas.

var country = {
cityName: "India", capital: "Dilhi", pm: "narendra modi", states: 28, 
};
document.write(country.cityName +" "+ country.pm )

  How to creat object is stated in the example above.

  In the example above the object (country) has four properties: cityName, capital, pm and states.

  The "country" is considered as an object as stated in the example

JavaScript Arrays data type

  An array is a type of object that is used to store multiple values in a single variable.

  JavaScript arrays are written with square brackets.

  JavaScript provides you with many ways to create an object. The object is most commonly used to use a literal sign.

  The array index starts at 0, so the first array component is arr [ 0 ] not arr [ 1 ].

let name = ["vikram", "hardik", "hitesh"];
document.write(name[0]);                   //output- vikram

• So get a brief overview of what JavaScript data tapes are and what its types are as mentioned above. We will now discuss all these types in detail in the next lecture.