ITIL edition / ServiceDesk Plus 7 ??

ITIL edition / ServiceDesk Plus 7 ??

Hello,

I've heard of ITIL edition and Service Desk Plus edition 7, are both the same? And what is the main differences between these and ServiceDesk Plus 6? If I have ServiceDesk Plus 6 can I upgrade later to ITIL edition or edition 7 ?? :?:

                    New to ADSelfService Plus?