ISO 14649-12:2005 specifies the technology-specific data elements needed as process data for turning. Together with the general process data described in ISO 14649-10, it describes the interface between a computerized numerical controller and the programming system (i.e. CAM system or shop floor programming system) for turning.

The subject of the turning schema, which is described in ISO 14649-12:2005, is the definition of technology-specific data types representing machining features and processes for turning operations on lathes.