What is the contents of the Model in the Model View Presenter (MVP) pattern

Question

Hi everybody,
I'm starting to use the Model View Presenter pattern. I read quite a lot and I have seen some examples. What is not very clear to me is what the contents of the Model should be. In some articles/examples it seems that the Model is member of the Presentation layer and only contains the data of the View. In other articles/examples it seems that the Model is member of the Data layer and contains the data related to the underlying database. Can someone give me some advice in this or give me some good examples? Thanks a lot!

Best regards,

Corné Albers