The range of Active Directory (AD) has expanded in Windows Server 2008 and has become an essential part of many information technology (IT) environments. Active Directory has become an umbrella for a multitude of technologies surpassing what AD was in Windows Server 2000 and 2003. Check out the new uses for Active Directory:
Active Directory Domain Services: An X.500-based directory service that provides integrated authentication and authorization services for a Windows computing environment.
Active Directory Lightweight Directory Services: A stripped down version of Active Directory Domain Services that focuses on providing just the directory services functionality.
Active Directory Federation Services: A Web Services–based technology for providing Web single sign-on authentication services between different organizations.
Active Directory Certificate Services: Provides digital certification enrollment and revocation services in the support of a public key infrastructure (PKI).
Active Directory Rights Management Services: Provides a solution for managing how users can use documents that they're authorized to access.