Both are possible.
Go to "View History" in the "Contacts" menu on the contact list
to view the history of all users - including offline users.
For webcam history, you need the item right below "View History" that
says "View Webcam Sessions".
No, I think you misunderstoond me. I'm sorry i've should have made myself more clear. It's not while the contacts are offline. It's when I am offline..
Thanks for your reply