What is the best way to start Unit and Functional testing of a Ruby Rails website?

describe "hello_world"
  it "should say hello to the world" do
    # RSpec comes with its own mock-object framework built in,
    # though it lets you use others if you prefer
    world = mock("World", :population => 6e9)
    world.should_receive(:hello)
    hello_world(world)
  end
end

Story: Commenting on articles

  As a visitor to the blog
  I want to post comments on articles
  So that I can have my 15 minutes of fame

  Scenario: Post a new comment

    Given I am viewing an article
    When I add a comment "Me too!"
    And I fill in the CAPTCHA correctly
    Then I should see a comment "Me too!"