require 'Stuff'     # loads Stuff module from Stuff.rb
                    # $: is a system variable -- contains the path for loads
class D
  include Stuff     # refers to the loaded module
  puts Stuff.m(4)
end

d = D.new
puts d.p(5)         # method p from Stuff 
puts $:             # array of folders to search for load
$: << "c:/"         # add a folder to the load path
puts $:
puts Stuff.m(5)     # Stuff class methods not called from D object