Abstract: The present invention provides a digital voice book library system which through Internet provides an customized digital audio version book that can be customized according to a learner's learning language, learning level, learning condition, learning taste or the like by a learner's selecting/varying audio attributes of the audio version book(digital audio file) associated with the equivalent printed script (hardcopy) version book that is owned by the learner or is borrowed from a conventional library or a book rental store. Wherein the audio attribute of said customized digital audio version book can be varied and customized in language, voice, speech speed or playback device at every repetition time according to user's learning language, learning level, learning condition or the like, corresponding to the equivalent script book despite different audio attribute.

Abstract: A system for providing customized audio content, based on a client-server communication network, includes a means for producing a plurality of audio content with different attributes; and a content-providing server for converting the plurality of audio content into digital audio files that are stored with and linked to the corresponding script. A contents file with specific attributes is provided via the communication network to a user after being requested.

Abstract: A system for providing customized contents, based on a client-server communication network, includes means for producing a plurality of audio contents with different attributes by recording a specific material as a script into at least one audio thereof; and at least one contents providing server for converting the plurality of said audio contents into digital audio files, storing together with the corresponding script file to be linked to each other in the contents providing means, and providing the contents file with specific attributes requested by a user in log-on via the said communication network.

Abstract: A computer, including: two mainboards, each comprising at least one CPU, RAM, video controller and hard disk; a connection device for peripheral devices selectively interconnecting connected peripheral devices to one of said two mainboards mounted within the same computer case by mainboard selection switch 6,7 thereof; at least one auxiliary storage device connected to said connection device for peripheral devices and selectively interconnected to one of said mainboards by mainboard selection switch 6,7 thereof; electric power supply device providing electric power to said two mainboards at the same time or selectively and to the auxiliary storage devices continuously; and a computer case comprising means of mounting said two mainboards, said connection device for peripheral devices, said electric power supply device, and said auxiliary storage devices within itself.