This type is the basis for all components and provides a base class for applications. Essentially it states that a component is a set of properties. This type is the basis for all components and provides a base class for applications. This type is the basis for all components that can be contained within a vcalendar component Events and todos only contain alarms Journal components contain no other components Freebusy components contain no other components Timezones only contain daylight and standard Standard components contain no other components Daylight components contain no other components Alarms contain no components