Which equals operator (== vs ===) should be used in JavaScript comparisons ?

Which equals operator (== vs ===) should be used in JavaScript comparisons?

In JavaScript, the == operator performs type coercion before making a comparison, while the === operator does not. This means that if you use ==, JavaScript will try to convert the operands to the same type before making the comparison.

For example, "5" == 5 will return true, because JavaScript converts the string "5" to the number 5 before making the comparison. However, "5" === 5 will return false, because the operands are not of the same type.

It is generally recommended to use the === operator for comparisons in JavaScript, as it provides a more predictable and consistent behavior. It also helps to avoid unexpected results caused by type coercion.

However, in some cases, using == can be useful, for example when comparing values with different types but that you want to consider equal, like comparing null and undefined.

In summary, use === operator when you want a strict comparison without type coercion, and use == when you want a comparison with type coercion.

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