~w sigil makes it easy to create a word list — a list of strings —
where each word is separated by a space.
> ~w(bulbasaur charmander squirtle) ["bulbasaur", "charmander", "squirtle"]
By appending an
a onto that sigil construct, you are instructing Elixir
that you would instead like a list of atoms.
> ~w(bulbasaur charmander squirtle)a [:bulbasaur, :charmander, :squirtle]