A reproducing method for reproducing audio-visual data, the method comprising: reading system data comprising menu information, the menu information comprising entry point information for audio-visual data to be reproduced for displaying a menu and mode information indicating whether a reproduction mode of the audio-visual data to be reproduced for displaying the menu is a program mode or a movie mode; determining a reproduction mode of the audio-visual data to be reproduced for displaying the menu by referring to the read mode information included in the menu information; reproducing a JAVA object referred to by the entry point information included in the menu information to reproduce the audio-visual data to display the menu when the determined reproduction mode is the program mode; and reproducing a movie object referred to by the entry point information included in the menu information to reproduce the audio-visual data to display the menu when the determined reproduction mode is the movie mode; characterised in that: reproducing the JAVA object comprises executing a plurality of JAVA application programs for providing additional functions using the audio-visual data in one or more titles in a title by title basis; and wherin the execution of the plurality of JAVA application programs is managed by management information corresponding to the JAVA object so that a life cycle of the plurality of JAVA application programs is managed in a title by title basis, the management information indicating at least one JAVA application program that can be executed in a title corresponding to the menu; and the management information for the title corresponding to the menu controls execution of the plurality of the JAVA application programs associated with the title corresponding to the menu. reading system data comprising menu information, the menu information comprising entry point information for audio-visual data to be reproduced for displaying a menu and mode information indicating whether a reproduction mode of the audio-visual data to be reproduced for displaying the menu is a program mode or a movie mode; determining a reproduction mode of the audio-visual data to be reproduced for displaying the menu by referring to the read mode information included in the menu information; reproducing a JAVA object referred to by the entry point information included in the menu information to reproduce the audio-visual data to display the menu when the determined reproduction mode is the program mode; and reproducing a movie object referred to by the entry point information included in the menu information to reproduce the audio-visual data to display the menu when the determined reproduction mode is the movie mode; characterised in that: reproducing the JAVA object comprises executing a plurality of JAVA application programs for providing additional functions using the audio-visual data in one or more titles in a title by title basis; and wherin the execution of the plurality of JAVA application programs is managed by management information corresponding to the JAVA object so that a life cycle of the plurality of JAVA application programs is managed in a title by title basis, the management information indicating at least one JAVA application program that can be executed in a title corresponding to the menu; and the management information for the title corresponding to the menu controls execution of the plurality of the JAVA application programs associated with the title corresponding to the menu. reproducing the JAVA object comprises executing a plurality of JAVA application programs for providing additional functions using the audio-visual data in one or more titles in a title by title basis; and wherin the execution of the plurality of JAVA application programs is managed by management information corresponding to the JAVA object so that a life cycle of the plurality of JAVA application programs is managed in a title by title basis, the management information indicating at least one JAVA application program that can be executed in a title corresponding to the menu; and the management information for the title corresponding to the menu controls execution of the plurality of the JAVA application programs associated with the title corresponding to the menu.