JavaScript Equality: When to Use `==` vs. `===`?

Distinguishing Between Equality Operators in JavaScript

In JavaScript, determining equality can be tricky, as there are multiple ways to do so. Understanding the nuances between the == and === operators is crucial to avoid unexpected results.

The == operator, "loose equality," tests if two values are equal but also coerces data types if necessary. For example, "0 == false" returns true because the operator converts the string "0" to the number 0.

In contrast, the === operator, "strict equality," checks if two values are equal and of the same type. It does not perform any type coercion. "0 === false" returns false because the values are not the same type.

Additionally, there are != and !== operators, which perform the opposite checks. != is "loose inequality," while !== is "strict inequality."

Here's a concise example:

0 == false   // true (loose equality)
0 === false  // false (strict equality)
1 == "1"     // true (loose equality)
1 === "1"    // false (strict equality)

By carefully selecting which equality operator to use, you can ensure that your JavaScript code behaves as expected, especially when dealing with different data types. For further elaboration, refer to the link provided in the answer.

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