what determines controller action ruby rails -

at https://www.codecademy.com/en/courses/learn-rails/lessons/start/exercises/start-views, controll action described 'pages#home':

well done! when user visits http://localhost:8000/welcome, route  'welcome' => 'pages#home'  tell rails send request pages controller's home action. 

but when made controller did rails generate controller pages uppercase.

pages_controller.rb:

class pagescontroller < applicationcontroller    def home   end  end 

1. is pages part of pages#home determined first part of pages_controller.rb, ignoring _controller.rb end?

2. what happens if change pages_controller.rb renamedpages_controller.rb leave class name pagescontroller?

thank you

1. yes. , #home "action" in pagescontroller
2. you uninitialized constant pagescontroller error

so, controllers should in form namecontroller defined in name_controller.rb, , actions public methods in namecontroller.