Difference between != and !== operator in JavaScript

!= operator
- The inequality operator (!=) is the logical opposite of the equality operator. It means “Not Equal” and returns true where equality would return false and vice versa.
- Like the equality operator, the inequality operator will convert data types of values while comparing.
- For example 1 != ‘1’ will return false since data type conversion take place so 1 and ‘1’ are considered equal.
!== operator
- The strict inequality operator (!==) is the logical opposite of the strict equality operator. It means “Strictly Not Equal” and returns true where strict equality would return false and vice versa.
- Strict inequality will not convert data types.
- For example 1 !== ‘1’ will return true since 1 is an integer and ‘1’ is a character and no data type conversion take place.

Example:

<script> 
    function NotEqual(val) { 
        if (val != 1) { 
            return "Both are Not Equal i.e. condition is true"; 
        } else { 
            return "Both are Equal i.e. condition is false"; 
        } 
    } 
  
function StrictlyNotEqual(val) { 
    if (val !== 1) { 
        return "Both are Not Equal i.e. condition is true"; 
    } else { 
        return "Both are Equal i.e. condition is false"; 
    } 
} 
  
//Passing integer 
  
console.log("  1 != 1 " + NotEqual(1)); 
console.log("  1 !== 1 " + StrictlyNotEqual(1)); 
  
//Passing character 
  
console.log(" '1' != 1 " + NotEqual('1')); 
console.log(" '1' !== 1 " + StrictlyNotEqual('1')); 
  
//Passing string 
  
console.log(" \"1\" != 1 " + NotEqual("1")); 
console.log(" \"1\" !== 1 " + StrictlyNotEqual("1")); 
  
//Passing false value i.e. 0 
  
console.log("  0 != 1 " + NotEqual(0)); 
console.log("  0 !== 1 " + StrictlyNotEqual(0));  
</script> 

Output:

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