A class, in general, is a representation of a concept. It is an abstract representation of some specific classification of things (hence the name class). The name used to identify a class is the perceptual symbol or word used to denote a concept. In an ontology, a class is more specifically a formal definition of a type of information object that may possess a given set of attributes or properties and specific types of relations to other things. The ontology class is the template for an instance or individual of that type. In other words, the class is the schema or model for information of a given type while an instance of the class is considered to be the actual data.