This repository contains the current version of the Hydrogen Ontology and all the resources generated througout its development. It's the code corresponding to the paper "HOLY: An Ontology covering the Hydrogen Market" The Hydrogen Ontology (HOLY), a domain ontology modeling the complex and dynamic structures of hydrogen-based markets. The hydrogen economy has become a politically and economically key sector for the transition to renewable energy, accelerating technological and socio-economic innovations. However, attainment of market insights requires a large variety of informational concepts which are predominantly found in unstructured text data. HOLY provides the necessary structure for the representation of these concepts. Through a top-down approach, HOLY defines taxonomies based on a hierarchical structure of products and applications. In addition, to ensure reusability, the ontology incorporates components from established ontologies in its structure. As a result, HOLY consists of over 100 classes storing information about organizations, projects, components, products, applications, markets, and indicators.