This <a href=”http://www.computerperformance.co.uk/w2k3/W2K3_server_roles.htm”>resource</a> might help answer your questions.
Here’s another list that might help answer this question.
* A stand-alone server does not have Active Directory® installed, and it’s not a member of an Active Directory® domain. Users will have to authenticate a stand-alone server when they want to access it.
* A domain controller has Active Directory® installed. All domain controllers store a copy of the domain database. They all participate in multi-master replication, and they authenticate users. Essentially, domain controllers control directory data and coordinate communication between users, servers and other domains on the network.
* A member server, like a stand-alone server, is not a domain controller in that it doesn’t have Active Directory® installed–but it is a member of an Active Directory® domain. A member server does not authenticate users. For a user to access a member server, they have to have been successfully logged into an Active Directory® domain.