Introduction (elements and processes of electric power systems and their basic characteristics, types of software applications and data models, basic processes of application integrations and data exchange, etc.). Structured and unstructured data (data model presentations, storage and software access tools). Models of electric power system data in industry (standards, data model presentations, etc.). Descriptions of data models (linked data, semantics, ontologies and reasoning). Querying and data analysis. Big Data concepts. Selected chapters in the field of machine learning applied in power systems.