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swolecoder
swolecoder

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JS Double Equals Vs Triple Equals

Triple Equals
It looks for both types and value

 - Both Number and equal values
     2  === 2 // true

 -  Both String and equal values
    “Hello” === “Hello” // true 

 - Both booleans and equal values 
    true === true  //true 

 - Number Vs String

    43 === ’43’ //false

 - Different types ( Boolean Vs Number)

   false === 0 //false 

Double Equals
It just looks for value. Double does type coercion which means it tries to convert them into common type before comparing.

   77 == ’77’ //true

   77 === ’77’ //false

   false === 0 //false

   false == 0 //true  

Falsy Values Comparison:
There are 6 falsy values in JS: false, 0, "", null, undefined and NaN

 false == 0 //true

 0 == “” // true

 “” == false //true

 null  == null //true

 undefined == undefined //true

 null == undefined // true  

 - Note: NaN is not equivalent to anything 


 NaN == NaN //false

 NaN == null //false

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