When to move a method into a helper, and when into a module?

Question

Ruby on Rails

Do I understand correctly that the general methods for models are taken out in separate modules, for example,
models/user.rb

class User < ActiveRecord::Base
include Confirmable
...
end

lib/confirmable.rb

module Confirmable
  def some_method 
     ...
  end
end

While common methods for controllers should be placed in application_helper.rb or other helpers?
What is the best practice of taking out a duplicate when is optimal for models and controllers?

Answer 1

For models and controllers, there are so-called concerns (Concerns), I think this is exactly what you need: artemeff.com/2013/04/21/concerns-v-rails-4.html

Answer 2

View Helpers