To enable a user to more pleasantly understand the instruction manual of a product and to accurately use the product by preparing a device which has a built-in instruction manual and an output device which outputs the instruction manual.

An interface cable 1 of an output device is connected to a product which has the built-in instruction manual. The voices of the output device are outputted and also the text, graphic forms, videos, etc., are outputted onto an output screen 2 to assist a user to understand the instruction manual. The instruction manual is built in the product and therefore never lost nor disused. Thus, the user can understand more pleasantly the instruction manual and also the maker of the product can secure the accurate use of the product to prevent the accidents which are cased by the product. Furthermore, just a single piece of this output device can deal with the products of all makers in every home as long as the least functions and specifications of the output device are standardized.