What does name parameter mean

Questions & Help Questions
1

Hi all
I have following module that implement GenServer, the code is from book elixir in action.

defmodule Todo.DatabaseWorker do
  use GenServer

  def start_link(db_folder, worker_id) do
    IO.puts "Starting database worker #{worker_id}"

    GenServer.start_link(
      __MODULE__, db_folder,
      name: via_tuple(worker_id)
    )
  end

 defp via_tuple(worker_id) do
    {:via, Todo.ProcessRegistry, {:database_worker, worker_id}}
  end
end

What I do not understand is the name parameter in the start_link function. What does it mean, why the function via_tuple function return a tuple?

Thanks