Apart from being a truly revolting word, calendaring is the word that Microsoft uses to describe the ability to programmatically manage calendars and schedules. So whereas the key messaging element in CDO for NTS is the 
 object, the full-blown implementation of CDO 1.2 also includes objects such as the Message
 object and the AppointmentItem
 object. These allow developers to build web pages which can interact with either Schedule+ or Outlook calendars (a single interface provides access to both) and so produce web-based applications which can be used for tasks such as sophisticated resource scheduling.MeetingItem