Biological and Medical Ontologies: Introduction

The increasing availability of biomedical-molecular data and information pushed the need for their standard descriptions, which allow their automatic processing for knowledge extraction. Towards this goal, many biological and medical terminologies and ontologies were developed, and actively used to describe the features of numerous biomedical-molecular entities. However, bio-terminology and bio-ontology development grew dispersedly and not uniformly, producing not matching ontologies with their annotations being non-comparable, hampering their interoperability role. These issues have been mostly overcome with the spread of Open Biological and Biomedical Ontologies, a set of well-structured and orthogonal bio-ontologies, and of the Unified Medical Language System, which provides mapping among biomedical concepts and relations from multiple sources.