When the Active DIRECTORY is installed on a server (MAKING it a domain controller), a set of Active Directory snap- ins is provided. The Active Directory Users and Computers snap-in is USED to manage Active Directory objects such as USER accounts, computers, and groups. The Active Directory Domains and Trusts snap-in enables you to manage the trusts that are defined between domains. The Active Directory SITES and Services snap-in provides for the management of domain sites and subnets. 

When the Active Directory is installed on a server (making it a domain controller), a set of Active Directory snap- ins is provided. The Active Directory Users and Computers snap-in is used to manage Active Directory objects such as user accounts, computers, and groups. The Active Directory Domains and Trusts snap-in enables you to manage the trusts that are defined between domains. The Active Directory Sites and Services snap-in provides for the management of domain sites and subnets.