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  • Ahmed Elgendy thinks this is interesting:

JavaScript is kind of loose about true and false. How is it loose? Well, there are values in JavaScript that aren’t true or false, but that are nevertheless treated as true or false in a conditional. We call these values truthy and falsey precisely because they aren’t technically true or false, but they behave like they are (again, inside a conditional).

From

Cover of Head First JavaScript Programming

Note

What are the value of Javascript that can be evaluated to truth and false (truthy and falsey) even though they are not technically true or false.