A user with the <em>Administer fields</em> permission for a certain entity type may add <em>Taxonomy term</em> reference fields to the entity type, which will allow entities to be classified using taxonomy terms. See the <a href=":entity_reference">Entity Reference help</a> for more information about reference fields. See the <a href=":field">Field module help</a> and the <a href=":field_ui">Field UI help</a> pages for general information on fields and how to create and manage them.