[Orgmode] Multi Todo state

[Chao LU]

Dear all,

Is it possible to have multiple todo state for one item? Like example below:

(setq org-todo-keywords '((type "PersonA" "PersonB" "PersonC" "|" "DONE")

                                      (sequence "REPORT" "BUG" "KNOWNCAUSE" "|" "FIXED")))

So it could be possible for one item both have "PersonA" and "BUG" todo properties. Besides, what's the essential difference between TODO and TAG? Since to me, TODO is kind of special TAG?

Thanks a lot.

Chao