The document is the fourth edition of 'An Introduction to Nursing Informatics,' 2021 DANATOTO edited by Kathryn J. Hannah, Pamela Hussey, Margaret A. Kennedy, and Marion J. Ball. It serves as a primer for nurses seeking foundational knowledge in nursing informatics, emphasizing the importance of informatics in modern healthcare and eHealth service delivery. The book includes contributions from various experts and aims to inspire critical thinking about nursing practice in the context of evolving health informatics technologies.