To enable a user to obtain an interactive operation environment by automatically displaying schedules and guidances of events on a bulletin board and retrieving, calculating and outputting event relevant data by the condition of a selecting operation when a user performed the selecting operation with a selection operating means to display even guidances or the like on the same display.

In a maintenance terminal device 20, event relevant data and display data or the like are stored in a data file part 23 by registeringly operating schedules, contents, guidances and display modes of events while using a registration operating part 22. Event relevant data and display data or the like of the data file part 23 are transmitted to a bulletin board device 1 via a communication line 43. The communication control part of the bulletin board device 1 receives various data to store them in a data memory part. Then, the device automatically displays schedules, guidances of regular events or the like and when the user has performed a selecting operation, the retrieving and calculating part of the device retrieves, calculates and outputs event relational data by the condition of the operation.