Ruby on Rails is MVC environment. The C part of MVC goes for Controller. This is the place where you define your actions. The are couple of standard actions, such are Index, Show, Update, Destroy, but you can obviously create any other one you need. There are two handy parameters you might want to setup before you specify your actions. The first one is layout type and the second one is before_filter.
The project controller would start like this.
class ProjectsController < ApplicationController #you can have different versions of layout so here you specify which one you want this controller to use when it is rendered #there is layouts directory in the views directory, you would find the standard.htm.erb file sitting in there layout 'standard' #here you can setup if the page can be accessed for strangers (users who are not logged in) #as you can see in my case it is not possible before_filter :login_required # this is how you would define action in rails def index end end