What is the optimal number of controllers for this?

Hi,

I'm still adjusting to Ruby on Rails and the MVC model. But I wanted
to query the group on what the best design is -- i.e. how many
controllers should I have for the following. A customer will register
on our site to order a product. After registration, or if they leave
and decide to log in again, they can place their orders through a pre-
built order form. After placing the order, they see a thank you
screen and receive a confirmation email.

What is the best number of controllers (and which ones) should I
create for this?

Thanks, - Dave

I would think you'll need 3.

Customers
Products
Orders

Each customer has_many orders, and each order has_many products. But
you also might need something for payments also, depending on how you
process them.

-Ryan