What are AD Snapshots? How do you use them?

Snapshots are a feature of Active Directory introduced in Windows Server 2008. In order to use them you don't have to have your domain running in Windows Server 2008 mode but you do need at least one Windows Server 2008 or Windows Server 2008 R2 domain controller.

Snapshots are created and manipulated using the ntdsutil.exe command line utility. Once you have an Active Directory snapshot you can export it using dsamain.exe (otherwise known as the Active Directory database mounting tool), and you can then interact with it using any Active Directory or LDAP tool.