This project would not have reached its current level of maturity without the generosity of numerous members of the ontology, semantic web, enterprise architecture, and knowledge graph communities.
Many people contributed through technical discussions, detailed chapter review, engineering suggestions, issue reports, and encouragement throughout the writing process.
The following individuals deserve special recognition.
Author of the original Protégé 5 New OWL Pizza Tutorial.
This book is built upon Michael’s excellent tutorial, which has served for many years as one of the most practical introductions to OWL ontology engineering.
Beyond creating the original tutorial, Michael has kindly provided valuable feedback on the direction of this book and has been supportive of extending the tutorial into a broader engineering perspective through the Semantic Knowledge Development Lifecycle (SKDL) and Executable Knowledge Architecture (EKA).
Without his original educational work, this project would not exist.
Founder & CEO, Axius SDC, Inc.
Tim has generously reviewed multiple chapters of this book during its development, particularly those concerning semantic governance, ontology engineering practice, and enterprise-scale knowledge systems.
His feedback has helped strengthen several important engineering themes throughout the SKDL framework, including:
His perspective comes from extensive real-world work in semantic interoperability, healthcare data standards, and enterprise semantic governance.
I am deeply grateful for his thoughtful reviews, constructive criticism, and continued encouragement throughout the writing of this book.
Many members of the broader ontology and semantic web community have contributed indirectly through discussions, questions, publications, conference presentations, open-source software, and years of accumulated research.
Protégé, OWL, RDF, Description Logic, and the Semantic Web ecosystem are the result of decades of collaborative work by thousands of researches and practitioners.
This book stands on the collective foundation.
Finally, sincere thanks to every reader who as reported errors, suggested improvements, opened GitHub issues, starred the repository, shared the project with others, or simply spent time learning ontology engineering through this book.
Every question, correction, and discussion helps improve future editions.
Knowledge grows through reuse, collaboration, and continuous refinement – the very principles promoted throughout this book.
Last updated at 2026-08-06