# 3.5.5 Model, ISO 42024 ## Published contents Contents1 Scope2 Normative references3 Terms and definitions4 Architecture concepts4.1 Overview4.2 Architecture and architecting4.3 Architecture design and solution design4.4 Architecture definition and communication4.5 Stakeholder concerns and architectural aspects4.6 Architecture viewpoints and architecture views4.7 Architecture frameworks and architecture description languages4.8 Architecture descriptions and architecture models4.9 Reference architectures and reference models4.10 Life cycle and life history4.11 Architecting precepts5 Architecting principles5.1 Introduction to the principles5.2 Principles about the purpose of an architecture5.3 Principles about the focus of an architecture5.4 Principles about architecting outcomesTerms 3.2 Architecting concepts 3.2.1 Architecture3.2.2 Architecture feature3.2.3 Architecting3.2.4 Architecting principle3.2.5 Architecture principle3.2.6 Architecture framework3.2.7 Reference architecture3.3 Entity related concepts 3.3.1 Entity of interest3.3.2 Solution entity3.3.3 Environment3.3.4 Context3.3.5 Enterprise3.3.6 System3.3.7 Aspect3.3.8 Dimension3.4 Architecture design concepts 3.4.1 Design (noun)3.4.2 Architecture design3.4.3 Architecture information package3.4.4 Engineering effort3.4.5 Solution design3.4.6 Solution information package3.4.7 Stakeholder3.4.8 Stakeholder perspective3.4.9 Concern3.5 Architecture description concepts 3.5.1 Architecture description3.5.2 Solution description3.5.3 Architecture view3.5.4 Architecture viewpoint3.5.5 Model3.5.6 Metamodel3.5.7 Reference model3.6 Entity life cycle concepts 3.6.1 Life cycle3.6.2 Life cycle phase3.6.3 Life cycle stage3.6.4 Life historyAnnexes A.1 Architecture design and solution related entitiesA.2 Architecture expressed as a set of modelsA.3 Life cycle and life history conceptsA.4 Enterprise and system conceptsA.5 Duality of architectural decomposition and architectural synthesisB.1 BackgroundB.2 Aligning architecture in designB.3 Duality of architectureB.4 Pursuit of opportunities Home / Glossary Architecture description concepts · 3.5.5 # Model A representation of one entity, or a group of entities, in the conditions or situations that matter. A model is typically used to portray, specify, understand or predict properties or characteristics. - definition - Term - ISO/IEC/IEEE DIS 42024 - Last updated: 2026-10-21 ## What this term settles A model represents, it does not become the entity. The phrase under conditions of interest is the important limit: a model is valid for those conditions, and a change in conditions can invalidate it without any change to the model itself. That is why models drift out of date in ways that are invisible in the tool. ## What to do in your practice Record for each model the entity it represents, the conditions it assumes and the purpose it serves. Add a review trigger for changes to those conditions. Treat a model outside its conditions as a hypothesis, not as evidence. Add the model conditions to the decision record, not only to the model register. A decision that depends on a model is only as good as the conditions the model assumed, and the decision record is where a later reader will test it. ## Who it binds The role that owns the practice area the term governs. A definition binds nobody on its own; it binds the reader who adopts the term in a method, a description or a contract. ## Evidence an auditor or regulator asks for - A model register with entity, conditions and purpose. An auditor asks what the model represents and when it was valid. - The conditions assumed by the model. Shows the limits of the evidence. - A review record when conditions changed. Shows the model was revalidated or retired. - The model version used in each decision. Lets a reviewer reproduce the decision. Ask your teamUnder what conditions is this model valid, and what has changed since it was last checked? ## Common gaps this page catches - Models are treated as the entity and are never revalidated. - The conditions of interest are not recorded. - Decisions cite a model without a version. ## What to prepare before publication Add a conditions line to the model register. Pick the model most used in decisions and test whether its conditions still hold. Record the result. ## Common questions What does Model mean in ISO 42024? A representation of one entity, or a group of entities, in the conditions or situations that matter. A model is typically used to portray, specify, understand or predict properties or characteristics. What evidence should we keep for 3.5.5? A model register with entity, conditions and purpose. The conditions assumed by the model. A review record when conditions changed. ## Related units - 3.5.6 - 3.5.7 - 3.3.7 Source. ISO/IEC/IEEE DIS 42024, Clause 3.5.5, Terms and definitions. Open the official record. Retrieved 21 October 2026. https://www.iso.org/obp/ui/en/#iso:std:iso-iec-ieee:42024:dis:ed-1:v1:en ISO catalogue record 87510, the status, stage and page count. Claim level: definition. The definition is in the public preview. This page states it in our own words and does not reproduce the text. Last updated: 2026-10-21 · Markdown version · Check your practice Source: https://iso-42024-revision-checker.theartofservice.com/glossary/model/