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JS DATA TYPES

DATA TYPES

 

PRIMITIVE               IMMUTABLE

NON PRIMITIVE     MUTABLE

COMPOSITE            COMBINATION OF PRIMITIVE & OTHER DATA TYPES

TRIVIAL                   PRE DEFINED VALUES

 

JS DATA TYPES

 

Java script data types are classified into following three types

1.      PRIMITIVE               NUMBER, STRING, BOOLEAN

2.      TRIVIAL                   NULL, UNDEFINED

3.      COMPOSITE            OBJECT, ARRAY

Number

Integer, Float, NaN

String  

Declared with single or double quotation

var a = " i am ok"  // i am ok

var b = "i 'm ok" // i'm ok

var c =  ' "guvi" ' // "guvi"

var d = "i am in \"the\" game"   // i am in "the" game

var e  = "i am in \' the game"    // i am in 'the game

Boolean

True or False

Boolean (0) ('')(null)(undefined)   =  false

Boolean (0.1) ('  ') = true

Undefined

var a; (without any value)

Null

var  a = null

Array [ ]

Helps to store list of data (it allow mixed data types also).

Index starts from Zero and length starts from the count 1

It consists only numbered index.

Object {  }

Named Index array (instead of [ ] declared inside {  })



  
typeof

Number

String 

Boolean

Undefined

Function

Object  --> Object, Array, Null

 

typeof(1)  -  number

typeof(1.1) - number

typeof("1.1") - String

typeof("JS")  - String

typeof(true) - Boolean    

typeof(null) - Object

typeof(undefined) - undefined

typeof([]) - object

typeof({}) - Object

typeof(NaN) - number

 


 

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