By maintaining a central data repository, Active Directory also allows users and applications to query objects and retrieve accurate data. If I need to find user John's account, I do not need to know which branch he is in, or to which department he belongs. With a simple Active Directory query, I will be provided with information about the user account. In a manner similar to when we add a new object to the directory, objects will publish their attributes and make them available to users and applications for queries.
These are some of the main capabilities of the Active Directory service, and these features will be explained in detail in later chapters, including how to plan, implement, and maintain them within your identity infrastructure.