An information providing device comprising: receiving means for receiving image data transmitted by an information processing device, the image data representing coded predetermined information; image recognition means for recognizing an image pattern in said image data; information detection means for detecting, from the image pattern recognized by the image recognition means, the coded predetermined information; information storage means for storing transmission information to be transmitted; information transmission means (12, 25) for transmitting a signal including predetermined transmission information of the transmission information stored in the information storage means corresponding to the coded predetermined information in a predetermined format to the information processing device; information output control means for controlling the information transmission means on the basis of the predetermined information detected by the information detection means so as to output the predetermined transmission information of the transmission information stored in the information storage means; access level setting means for setting an access level from the information processing device in accordance with access level information and authentication information included in the image pattern recognized by the image recognition means, wherein when the image recognition means does not recognize the image pattern, the information providing device transmits predetermined transmission information stored in the information storage means to the information processing device, and wherein when the image recognition means recognizes the image pattern and then the access level and authentication information are detected by the information detection means, the information providing device provides information to the information processing device corresponding to the access level and the authentication information on the basis of the result of detection. receiving means for receiving image data transmitted by an information processing device, the image data representing coded predetermined information; image recognition means for recognizing an image pattern in said image data; information detection means for detecting, from the image pattern recognized by the image recognition means, the coded predetermined information; information storage means for storing transmission information to be transmitted; information transmission means (12, 25) for transmitting a signal including predetermined transmission information of the transmission information stored in the information storage means corresponding to the coded predetermined information in a predetermined format to the information processing device; information output control means for controlling the information transmission means on the basis of the predetermined information detected by the information detection means so as to output the predetermined transmission information of the transmission information stored in the information storage means; access level setting means for setting an access level from the information processing device in accordance with access level information and authentication information included in the image pattern recognized by the image recognition means, wherein when the image recognition means does not recognize the image pattern, the information providing device transmits predetermined transmission information stored in the information storage means to the information processing device, and wherein when the image recognition means recognizes the image pattern and then the access level and authentication information are detected by the information detection means, the information providing device provides information to the information processing device corresponding to the access level and the authentication information on the basis of the result of detection.