An information processing device including: a data processing unit that generates an encryption key of content; and a communication unit that transmits an encryption key generated by the data processing unit, wherein the data processing unit generates, as the encryption key, individual keys that are different for each new content recording processing on a recording medium in a content recording device, and transmits the individual keys through the communication unit.

Compressed entertainment content such as audio or video or both includes additional aspects and operations associated their way. The compressed audio may be used to signal computers such as a telephone or reminder for an appointment. A melody line may be extracted from the audio, or the audio may be used exactly as it is. Another aspect stores traders within the entertainment content such as in MP3. Those traders are used to trigger the system to retrieve other parts of the content to be displayed at the same time that that particular part of the MP3 is being play. The content may include video or text, or maybe links to other content such as broadband content four times sensitive content. Another aspect describes encryption which is keyed to the disk ID to prevent playing oven illegally copied disk. Another aspect reads a specified amount of information then spins down the disk to conserve battery power.