To create attributes, you can use attr_reader and attr_writer methods followed by a symbol (a name preceded by a colon):
attr_reader :description attr_writer :description
You should add this code inside your class definition like this:
class Thing attr_reader :description attr_writer :description # maybe some more methods here... end
Calling attr_reader with a symbol creates a get accessor named description for an instance variable (@description) with a name matching the symbol :description.
Calling attr_writer creates a set accessor for an instance variable.
Instance variables are considered to be the "attributes" of an object.