Directory services are used to store and retrieve information about objects, which are managed by the service. On a network, these objects can include user accounts, computer accounts, mail accounts, and information on resources available on the network. Because these objects are organized in a directory structure, you can manage them by accessing various properties associated with them. For example, a person s account to use the network would be managed through such attributes as their username, password, times they re allowed to logon, and other properties of their account. By using a directory service to organize and access this information, the objects maintained by the service can be effectively managed.

The concept of a directory service can be somewhat confusing, until you realize that you ve been using them for most of your life. A type of directory that s been around longer than computers is a telephone directory, which organizes the account information of telephone company customers. These account objects are organized to allow people to retrieve properties like the customer s name, phone number and address.

Directory services shouldn t be confused with the directory itself. The directory is a database that stores data on the objects managed through directory services. To use our telephone directory example again, consider that the information on customer accounts can be stored in a phonebook or electronically in a database. Regardless of whether the information is accessed through an operator or viewed online using a 411 service, the directory service is...