1. A machine-implemented authoring method for a high definition digital versatile disc (HD DVD) utilizing an interactive application for the HD DVD, comprising: a) receiving a user-specified title of a video; b) enabling a user to specify an initial playlist file and at least one application for the HD DVD, the initial playlist file being one of a template-generated raw playlist file and a user-authored raw playlist file, the at least one application for the HD DVD including interactive content comprising one or both of receiving user inputs and displaying prompt messages; and c) in response to a user-inputted command, modifying the initial playlist file to set a corresponding relationship between the user-specified title and said at least one application for the HD DVD such that, during playback of the video having the user-specified title using the HD DVD, said at least one interactive application set to correspond to the user-specified title can be invoked and executed, wherein execution of the application includes allowing an audience of the video playback to simultaneously interact with the application in real-time via one or both of the user inputs and the prompt messages without interrupting playback of the video.