Ontologies are basically organized sets of controlled vocabulary terms that are applied in a uniform manor across diverse collections of information. They are important because of their ability to make abstract biological terms computer searchable. They also aid in the interpretation of biological information by researchers because each term includes a definition of how and when it should be applied to biological information. In this tip I briefly touch on finding ontologies, and on the educational resources available from the NCBO and BioPortal web sites.