What is collection and what is member?

Question

What is collection and what is member?

resources :photos do
  member do
    get :preview
  end
end

vs

resources :photos do
  collection do
    get :search
  end
end

Answer 1

The first one let you request [GET]:

/photos/1/preview

# action 'preview' within PhotosController with params[:photo_id] == 1

The second one let you request [GET]:

/photos/search

# action 'search' within PhotosController