what kind of OSs can be installed into Z/VM?

[legolas wood]

Hi
Thank you all for reading my post
Can some one please point me to a book which explains about Z/VM and 
also tell me what kind of OSs can be installed into Z/VM? A book that 
explain basics that a new user needs.

For example does any linux like ubuntu can be installed or just specific 
kind of linux can?

Thanks