I'm not a huge fan of the BOL article referenced, http://msdn2.microsoft.com/en-us/library/ms178134.aspx. I answered the question as the author of the question intended, so I'm a bit biased, but I think that BOL calling CLR a type of trigger, just like AFTER or INSTEAD OF, is logically inconsistent. CLR is just a means for creating a DML or DDL trigger, which I think is supported by other descriptions elsewhere in BOL, including the oft-cited article in this thread. And what does 'type' actually mean? In this case it seems to mean WHEN the trigger should do its action....that is until you bring CLR into it. CLR does not answer WHEN but rather how the trigger is created.

Anyway, I still think that BOL article is bad, adds nothing to the understanding of triggers, and the information in it could probably be rolled into both the descriptions for DML and DDL triggers as well as articles on creating triggers using CLR.