# Function model ## Links (Wikipedia order) <!-- injected from _registry/childlinks/Function_model.json (2026-07-30T02:09:12Z) --> `Abstraction_(computer_science)` · `Activity_diagram` · [[Aerospace_engineering]] · `Agile_software_development` · `American_Society_of_Mechanical_Engineers` · [[Arthur_David_Hall_III]] · `Aspect-oriented_programming` · `Axiomatic_design` · `Backward_compatibility` · `Bell_Labs` · [[Benjamin_S._Blanchard]] · [[Biological_systems_engineering]] · [[Block_diagram]] · `Business` · `Business_Process_Model_and_Notation` · [[Business_process]] · `Business_process_modeling` · `Business_reference_model` · `CI/CD` · `Capability_Maturity_Model_Integration` · [[Cognitive_systems_engineering]] · `Compatibility_layer` · `Compatibility_mode` · `Component-based_software_engineering` · `Computer_compatibility` · [[Computer_engineering]] · [[Computer_hardware]] · [[Computer_programming]] · [[Computer_science]] · [[Configuration_management]] · [[Control_engineering]] · `Copyright_status_of_works_by_the_federal_government_of_the_United_States` · `Core_business` · `Data_and_information_visualization` · `Data_model` · `Data_modeling` · `Data_structure` · [[Decision-making]] · `Decomposition_(computer_science)` · [[Derek_Hitchins]] · [[Design_review]] · `DevOps` · `Diagram` · `Douglas_T._Ross` · [[Earth_systems_engineering_and_management]] · [[Electrical_engineering]] · `Empirical_software_engineering` · `Enterprise_architecture` · [[Enterprise_systems_engineering]] · `Enterprise_unified_process` · `Entity–relationship_model` · `Essential_systems_analysis` · `Executable_UML` · `Experimental_software_engineering` · `Extreme_programming` · [[Fault_tolerance]] · `Federal_Aviation_Administration` · `Flow_diagram` · `Flow_process_chart` · `Formal_methods` · `Forward_compatibility` · [[Function_(engineering)]] · `Function_(mathematics)` · `Function_composition` · `Functional_block_diagram` · `Functional_decomposition` · `Functional_flow_block_diagram` · `Functional_specification` · `Government_agency` · [[Harold_Chestnut]] · [[Health_systems_engineering]] · [[Hierarchy]] · [[IDEF]] · `IDEF0` · `ISO/IEC_15504` · `Incremental_build_model` · [[Industrial_engineering]] · [[Information_model]] · [[Information_science]] · [[Information_system]] · `Interface_(computing)` · `Iterative_and_incremental_development` · [[James_S._Albus]] · `John_Mylopoulos` · [[John_N._Warfield]] · [[Joseph_Francis_Shea]] · [[Kathleen_Carley]] · [[Katia_Sycara]] · [[Manuela_M._Veloso]] · [[Manufacturing]] · [[Mathematical_optimization]] · `Matrix_(mathematics)` · `Mental_model` · [[Metamodeling]] · `Model-driven_engineering` · `Modeling_language` · `Multilevel_Flow_Modeling` · `NASA` · `Object-oriented_programming` · `Object_Management_Group` · `Object_model` · [[Ontology_(information_science)]] · `Operations_management` · [[Operations_research]] · `Organizational_structure` · `Performance_engineering` · `Polynomial_and_rational_function_modeling` · `Programmable_logic_controller` · `Programming_paradigm` · `Project_Gemini` · [[Project_management]] · `Quality_function_deployment` · `Quality_management` · [[Radhika_Nagpal]] · `Rapid_application_development` · `Reference_model` · [[Reliability_engineering]] · [[Requirements_engineering]] · `Risk_management` · `Robert_E._Machol` · `Role` · `Round-trip_engineering` · `Ruzena_Bajcsy` · [[Safety_engineering]] · [[Search-based_software_engineering]] · `Semantics` · `Service-oriented_architecture` · `Simon_Ramo` · [[Site_reliability_engineering]] · `Social_software_engineering` · `Software` · `Software_archaeology` · [[Software_architecture]] · `Software_configuration_management` · `Software_deployment` · `Software_design` · `Software_development_process` · [[Software_engineering]] · `Software_incompatibility` · `Software_maintenance` · `Software_prototyping` · [[Software_quality]] · [[Software_quality_assurance]] · `Software_system` · `Software_testing` · `Software_verification_and_validation` · `Spare_part` · `Spiral_model` · [[Stanford_torus]] · `Structure_chart` · `Structured_analysis` · `Structured_analysis_and_design_technique` · `Syntax` · [[System]] · [[System_dynamics]] · `System_integration` · [[System_of_systems_engineering]] · `Systems_analysis` · `Systems_development_life_cycle` · [[Systems_engineering]] · `Systems_modeling` · `Systems_modeling_language` · `TRW_Inc.` · `Task_analysis` · `Unified_Modeling_Language` · `Unified_process` · `Universal_Systems_Language` · `V-model` · `V-model_(software_development)` · `Varun_Grover_(information_scientist)` · `Verification_and_validation` · `View_model` · `Waterfall_model` · [[Wayback_Machine]] · `Wernher_von_Braun` · `William_Gosling_(engineer)` · `William_J._Kettinger` · `Wolt_Fabrycky` · [[Work_breakdown_structure]] · `Workflow` ## From the Real GENERATIVE library  *Function model — placed from the Real G.E.N.E.R.A.T.I.V.E. course library (Engineering room). Source: Wikimedia Commons (via Wikipedia article media). [Details & license](https://commons.wikimedia.org/wiki/File:IDEF_Diagram_Example.jpg).*  *Animated: Function model — placed from the Real G.E.N.E.R.A.T.I.V.E. course library (Engineering room). Source: Wikimedia Commons (via Wikipedia article media). [Details & license](https://commons.wikimedia.org/wiki/File:IPO-S_Model.gif).* > In systems engineering, software engineering, and computer science, a function model or functional model is a structured representation of the functions (activities, actions, processes, operations) within the modeled system or subject area.[1] ([Wikipedia](https://en.wikipedia.org/wiki/Function_model)) <!-- REAL-GENERATIVE-MEDIA:END --> > Summary stub · part of [[System]] · [Wikipedia source](https://en.wikipedia.org/wiki/Function_model) ## Summary In [[Systems_engineering|systems engineering]], [[Software_engineering|software engineering]], and [[Computer_science|computer science]], a function model or functional model is a structured representation of the functions (activities, actions, processes, operations) that the modeled system or subject area performs or comprises. Function models map the transformations and processes that a system executes, showing what functions occur, in what [[Sequence|sequence]] or relationships, and often with what inputs and outputs, creating an abstract representation of system behavior independent of how those functions are physically implemented. Function models serve as a bridge between high-level requirements and detailed design, enabling stakeholders to understand what a system does before specifying how it does it. Functional modeling is a core practice in systems engineering, helping teams align on system objectives, identify interfaces and interactions, and ensure that design choices support required functionality while managing [[Complexity|complexity]] through hierarchical decomposition of functions into sub-functions. ## Key points - Structured representation of functions, processes, and activities within a system - Maps transformations, sequences, and relationships among system functions - Bridges requirements and design by clarifying what the system does before specifying how - Enables identification of system interfaces, interactions, and functional dependencies - Hierarchical decomposition of functions manages complexity while ensuring coverage of requirements ## Relation to System Function models exemplify [[Systems_thinking|systems thinking]] by representing a system as a network of interdependent processes and transformations rather than isolated components. By explicitly representing functional relationships and dependencies, function models reveal where changes in one function affect others, supporting integrated system design that accounts for cascading effects. ## Sources - [Function model — Wikipedia](https://en.wikipedia.org/wiki/Function_model) Back to [[System]] --- <!-- SEMIOTIC-PROFILE:START --> ## Semiotic profile > *The semiotic universals this article invokes, machine-derived from the crossref — **unverified** (born so). Populated 2026-07-06 for the Systems room.* **Universals (6):** 🟡 system (18) · 🟡 sequence (3) · 🟢 transformation (3) · 🟢 tree hierarchy (2) · 🟡 science (1) · 🟢 network (1) **Enter by sign:** Systems Semiotic Gateway · Alphabetum · Icon Registry · ← Systems Portal <!-- SEMIOTIC-PROFILE:END --> <!-- REAL-GENERATIVE-MEDIA:START --> ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Function_model) : [Wikitube](https://en.wikitube.io/wiki/Function_model) ## Previous hub tags Tree parents: [[Reliability_engineering]] · [[System_dynamics]] · [[Systems_engineering]]. Legacy hubs: none. --- *Sources: 1 legacy note. Minted wave 1, 2026-07-30 (v1.6 order).*