.. _pre_defined_entity_types: Pre-defined entities in the library ----------------------------------- The library defines a set of entity schemas that are required by the system or commonly used in *CubicWeb* instances. Entity types used to store the schema ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * _`CWEType`, entity type * _`CWRType`, relation type * _`CWRelation`, relation definition * _`CWAttribute`, attribute relation definition * _`CWConstraint`, `CWConstraintType`, `RQLExpression` Entity types used to manage users and permissions ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * _`CWUser`, system users * _`CWGroup`, users groups Entity types used to manage workflows ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * :ref:`Workflow `, workflow entity, linked to some entity types which may use this workflow * _`State`, workflow state * _`Transition`, workflow transition * _`TrInfo`, record of a transition trafic for an entity Other entity types ~~~~~~~~~~~~~~~~~~ * _`CWProperty`, used to configure the instance * _`EmailAddress`, email address, used by the system to send notifications to the users and also used by others optionnals schemas * _`Bookmark`, an entity type used to allow a user to customize his links within the instance * _`ExternalUri`, used for semantic web site to indicate that an entity is the same as another from an external site