As defined by Microsoft, in Active Directory
server roles, computers that function as servers within a domain can have one of
two roles: member server or domain controller. A member server is a computer
that runs an operating system in the Windows 2000 Server family or the Windows
Server 2003 family, belongs to a domain, and is not a domain controller. Member
servers typically function as the following types of servers: file servers,
application servers, database servers, Web servers, certificate servers,
firewalls and remote-access servers.
