Answer Description
Microsoft Active Directory is a directory service for organizing user accounts, servers and client operating systems. Additionally it provides helpful features like enforcing password policies, running login scripts, applying user account restrictions and much more.
Wikipedia
Active Directory (AD) is a directory service developed by Microsoft for Windows domain networks It is included in most Windows Server operating systems as a set of processes and services Initially, Active Directory was used only for centralized domain management However, Active Directory eventually became an umbrella title for a broad range of directory-based identity-related servicesA server running the Active Directory Domain Service (AD DS) role is called a domain controller It authenticates and authorizes all users and computers in a Windows domain type network, assigning and enforcing security policies for all computers, and installing or updating software For example, when a user logs into a computer that is part of a Windows domain, Active Directory checks the submitted password and determines whether the user is a system administrator or normal user
Active_Directory - Wikipedia, the free encyclopedia