Active Directory Schema

The Microsoft® Active Directory™ schema contains formal definitions of every object class that can be created in an Active Directory forest. The schema also contains formal definitions of every attribute that can exist in an Active Directory object.

This section provides an overview of the Active Directory schema, including the following topics:

• Schema Implementation
• Characteristics of object classes
• Characteristics of attributes
• The abstract schema, which provides a convenient way to retrieve the most frequently used information in a class or attribute definition.

For information on schema programming, including reading the schema and defining new classes and attributes in the schema, see Extending the Schema.

For reference pages for the predefined schema classes, attributes, and attribute syntaxes, see Active Directory Schema Reference in the Active Directory Reference.