CComDynamicUnkArray Manages unlimited connections between a connection point and its sinks.
CComUnkArray Manages a fixed number of connections between a connection point and its sinks.
CFirePropNotifyEvent Notifies a client’s sink that an object’s property has changed or is about to change.
IDispEventImpl Provides support for connection points for an ATL COM object. These connection points are mapped with an event sink map, which is provided by your COM object.