Okey, so the first thing everyone should learn is not to use "==" but use "===". Or, perhaps, just use TypeScript, right? I think that's what people call "effective JavaScript" these days.
Quite a lot can be built reliably with Javascript following only "use ===". YMMV. Typescript doesn't solve much unless you use it religiously (and few people really do), it still allows for all kinds of "gotchas" if you want to write "gotchas" with it.
