Differences between "Role-Object Pattern" and "Type-Object Patern"

I'm studying for university and I have to learn the difference between "Role-Object Pattern" and "Type-Object Patern" (Purpose and Class diagram).

I don't find any difference between them. I believe the class diagram is the same, but the purpose is different (I think). So, I don't understand this last.

How can I realize which of them I have to use?

I'm confused.

Thanks.