Card windowing metaphor for application command and presentation history

摘要

An information processor, which manages operational history data or status data to revert an application back to any desired point in the past or make use of the past operations, includes an interface screen having cards thereon, as objects, that are manipulated by a user so as to make use of history. Contents of the history are represented while the order of the cards, placed one upon another, is associated with the time series of the history. A card representation is provided on the screen presented by the application to the user at any point in a past or to provide a card representation defined by images which alternately display screen representations before and after a change in the application screen by the operation performed by the user at any point in the past, while the before-change and after-change representations are displayed for different periods of time. A tag provided to the card is incorporated in the interface screen and objects of stacks, where a bundle of cards arranged according to the time series of the card history is placed and to which instructions as to a user's operation performed on the card bundle are inputted, are incorporated on the user's interface screen. The stack cooperates with the application by letting the application execute an operational history corresponding to a card sequence on the stack and letting the results be represented on the cards; and the card sequence is inserted into the stack in conjunction with the application; thereby, letting the application execute the operational history.