Include vs Extend

include_vs_extend.rb

module FlippedTable
  def table
    "┻━┻"
  end
end

class AngryTableFlipper
  # Including FlippedTable's methods...
  # as instance methods
  include FlippedTable

  def table_flip
    # Call table method
    "(ノಠ益ಠ)ノ彡" + table
  end
end
# => "(ノಠ益ಠ)ノ彡┻━┻"

AngryTableFlipper.new.table_flip

class ClassyTableFlipper
  # Extending FlippedTable's methods...
  # as class methods
  extend FlippedTable

  def table_flip
    # Call table class method from the class itself
    "(╯°□°）╯" + self.class.table
  end
end

ClassyTableFlipper.new.table_flip
#  => "(╯°□°）╯┻━┻"