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JS DATA TYPES

 

JS DATA TYPES - Basics


PRIMITIVE               IMMUTABLE

NON PRIMITIVE     MUTABLE

COMPOSITE            COMBINATION OF PRIMITIVE & OTHER DATA TYPES

TRIVIAL                   PRE DEFINED VALUES

 

Java script data types are classified into following three types

1.      PRIMITIVE               NUMBER, STRING, BOOLEAN

2.      TRIVIAL                   NULL, UNDEFINED

3.      COMPOSITE            OBJECT, ARRAY

 

NUMBER

int,float

STRING

 ‘word’

“Words” 

‘5’

“Everything inside the quote”

BOOLEAN

True

False

ARRAY

[]

container  used to store list of data

Mixed data types

Numbered Index

[1,2,3,a,b,c]

OBJECT

{}

{“name”: “Happy” , “Place”:“Youtube”}

Named Index

NULL

UNDEFINED

 

NULL VS UNDEFINED

var a ;      (undefined  - nothing)

var b = null; (null – Something)

var c=5;

var d = a+c // NaN

var e = b+c  //5

null !== 0;    undefined !==0;

 


 


 


 

How to write Quotes Inside String Data Type

 I ‘m  here

“ Happy Learning “

 

METHOD 1 –  Opposite Quotation

“I ‘m  here “

‘ “ Happy Learning “ ‘

 

METHOD 2 –  Backslash

‘ I \’m  here ‘

‘ \“ Happy Learning \“ ‘

This method is suitable for text editor only not for console

 

 

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