Help with Application.get_env data type key

I am investigating an opensource project which makes a call like this:

    url = Application.get_env(:hailstorm, Hailstorm)[:host_web_url] <> path

Full source:
Line 23

What is the variable Hailstorm data type? It’s doesn’t look like a string or atom.

It’s an atom, more specifically: :"Elixir.Hailstorm"


Identifiers that start with uppercase letters are simply atoms! They don’t have to point to modules which is why you could type Foo in iex and not get an error.