crayment/categories_controller.rb

## categories_controller.rb
class CheckoutsController < ApplicationController
  def index
    @categories = Category.all
  end
end

## index.html.erb
<% @categories.each do |cat| %>
  <p><%= cat.name %></p>
<% end %>
	class CheckoutsController < ApplicationController
	def index
	@categories = Category.all
	end
	end
	<% @categories.each do \|cat\| %>
	<p><%= cat.name %></p>
	<% end %>