I just happened upon singleton classes, and was wondering two things:

1) There's no difference between these two codes, right?  Is there an
advantage or disadvantage over either?  Does Ruby put bar() into the
same virtual class object for both?

class Foo
  class << self
    def bar
    end
  end
end

class Foo
  def self.bar
  end
end

2) A singleton class has nothing to do with the singleton design
pattern, right?  They only share the same name because there is only
ever one of them.