Abstract: A conversational-type programming apparatus well suited for use when data are to be input in response to prompts on a conversational display in order to create a partial program, is provied. When a predetermined parameter item has been selected, the details of the selected item can be correctly understood, even by a person who is not skilled in NC programming language, thanks to a display of auxiliary graphics corresponding to the selected item. This enables an operator to input machining data while referring to auxiliary graphics corresponding to the parameter items, as a result of which the operator can rapidly become skilled at determining inputs.