what is "line_items"?

hi guys,
I am looking at http://railscasts.com/episodes/141-paypal-basics and
I am trying to figure out what's line_items?

Is it a reserved keyword representing a row of a multi row form or is
it just a variable that's called line_items (and is not a reserved
keyword)?

If it is a reserved keyword/function in rails, can someone please
point me to some documentation?

thanks

Gordon

line_items is a model/table.

class LineItem < ActiveRecord::Base
  belongs_to :cart
  belongs_to :product

  def full_price
    unit_price * quantity
  end
end

ah right. So it is a user defined model. Am I right?

Yes, it’s a user defined model.

-Conrad