Do you find difficulty choosing between =, == & === ?

Assigning Operator (=)

It assigns the value to the variable.

const firstName = 'Prashant';
const favNumber = 13;

Loose Equality Operator (==)

This operator compares two values & return true if they are equivalent or false if they are not.

function equality(value) {
     if(value == 13) {
          return 'Equal';
     }
     return 'Not Equal';
}

In addition, it also compares two different data types (numbers & strings).

It is called as Type Coercion.

1 == '1' /* This will return true with the Loose Equality Operator. */

Strict Equality Operator (===)

Unlike the Equality Operator, it does not compare two different data types.

Otherwise, it works similarly to Loose Equality Operator.

1 === '1' /* This will return false in case of the Strict Equality Operator. */

More Examples

var favBook = 'Sapiens'; /* Assigns the value to the variable */

const 13 == '13'; /* It will perform a type conversion and it will return true. */

const 13 ==='13' /* It will not perform type conversion. Hence, it will return false. */

A tip by

[Deleted User]

Ideally, you should always use === and !==, and never use ==, and !=.
Or to make it easy to use what can you do is configure your linter to always use === and !== in code editor.
The loose equality has too many pitfalls that are covered by the strict one.

Hope you found it helpful. Please let me know.

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Comments

[Prashant Patel]

Thanks for sharing this great tip Luke. Adding this into article!