What does console.log([] == ![]) output?

Console output

Why

First ![] evaluates: arrays are always truthy, so ![] is false. Now it is [] == false. Loose equality coerces booleans to numbers, so false becomes 0. Then [] coerces to a primitive (empty string ""), which becomes 0. So 0 == 0 is true. A classic demonstration of how confusing == can be.