active-directory-schema.md

title	description	ms.assetid	ms.tgt_platform	keywords	ms.topic	ms.date
Active Directory Schema (AD DS)	The 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.	b901d095-6805-439b-94b0-05af39594126	multiple	Active Directory Schema	article	05/31/2018

Active Directory Schema (AD DS)

The 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.

Topics that provide an overview of the Active Directory schema include:

• Schema Implementation
• Characteristics of Object classes
• Characteristics of Attributes
• The Abstract Schema

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

For more information, see the Active Directory Domain Services Reference. For the reference pages for the predefined schema classes, attributes, and attribute syntaxes, see the Active Directory Schema Reference.