Entities that are formally defined and are considered independent from the social context in which they are used. They cannot be localized in space or time. Also called 'Platonic entities'. Mathematical and logical entities are included in this class: sets, categories, tuples, costants, variables, etc. Abstract formal entities are distinguished from information objects, which are supposed to be part of a social context, and are localized in space and time, therefore being (social) objects. For example, the class 'Quark' is an abstract formal entity from the purely set-theoretical perspective, but it is an InformationObject from the viewpoint of ontology design, when e.g. implemented in a logical language like OWL. Abstract formal entities are also distinguished from Concept(s), Collection(s), and Description(s), which are part of a social context, therefore being SocialObject(s) as well. For example, the class 'Quark' is an abstract FormalEntity from the purely set-theoretical perspective, but it is a Concept within history of science and cultural dynamics. These distinctions allow to represent two different notions of 'semantics': the first one is abstract and formal ('formal semantics'), and formallyInterprets symbols that are about entities whatsoever; for example, the term 'Quark' isAbout the Collection of all quarks, and that Collection isFormalGroundingFor the abstract class 'Quark' (in the extensional sense). The second notion is social, localized in space-time ('social semantics'), and can be used to interpret entities in the intensional sense. For example, the Collection of all quarks isCoveredBy the Concept 'Quark', which is also expressed by the term 'Quark'.