I left that out because some commenters mentioned that as the leading feature. But for somebody who's asking what Node.js is used for, I don't think being asynchronous is as important a reason as the fact you're writing JavaScript with great tooling, frameworks, and modules.

As far as coding day-to-day, there are other languages that have better semantics around writing asynchronous code. And it rarely makes a difference for first-time developers until they actually build something and try to scale, and at that point would need to read articles about doing that with Node.js just like they would with Ruby/Rails, Clojure, Go, etc.