Active Directory is a directory service created by Microsoft for Windows domain networks. It is included in most Windows Server operating systems.

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Active dierectory is a centralised database which has the permisions user accounts if we create any user in active dierectory it will be saved in a ad unlike wok group it will not be saved in local conputers hard disk it can accessed by the all users in the company based on thier permisions created by the ad administrator

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Active Directory is a technology created by Microsoft that provides a variety of network services, including:

LDAP-like[1] directory services
Kerberos-based authentication
DNS-based naming and other network information
Central location for network administration and delegation of authority [2]
Information security and single sign-on for user access to networked based resources [3]
The ability to scale up or down easily [4]
Central storage location for application data [5]
Synchronization of directory updates amongst several servers [6]
Using the same database, for use primarily in Windows environments, Active Directory also allows administrators to assign policies, deploy software, and apply critical updates to an organization. Active Directory stores information and settings in a central database. Active Directory networks can vary from a small installation with a few computers, users and printers to tens of thousands of users, many different domains and large serve ...more

A central component of the Windows platform, Active Directory directory service provides the means to manage the identities and relationships that make up network environments.