Active Directory™ is Microsoft's trademark directory service; it is a central component of the Windows platform. Active Directory's directory service provides the means to manage the identities and relationships that make up network environments. Active Directory is an LDAP-compliant directory supporting the core LDAP specifications.

LDAP (Lightweight Directory Access Protocol) is a protocol used to access a directory and through that enable users or programs to locate people, organizations, and other resources in an Internet or intranet directory. The protocol could be used for retrieving information such as addresses, phone numbers, etc. from a corporate address book.

An LDAP directory is a hierarchical directory of names that can reflect an organization's structure or geography and that is accessed via the LDAP protocol.