Huvudfunktion

Huvudfunktion is a term used in Swedish to denote the main function or core purpose of a system, device, process, or organization. It refers to the essential operation that the entity is designed to perform, differentiating it from secondary features, ornamental aspects, or auxiliary capabilities. In practice, identifying the huvudfunktion helps stakeholders understand what the product must do to satisfy user needs and to guide design, implementation, and testing.

Examples illustrate its use: a calculator's huvudfunktion is to perform arithmetic calculations; a word processor's huvudfunktion is to enable creation and editing of text documents; a vehicle's huvudfunktion is to provide safe and efficient transportation, while additional features like entertainment systems are secondary.

In software engineering, the huvudfunktion is a focal point of the requirements specification. It is used to derive functional requirements, acceptance criteria, and test cases. A well-defined huvudfunktion is observable, measurable, and dependable under expected conditions; it may require balancing with nonfunctional requirements such as performance, reliability, and security.

Complex systems may have multiple huvudfunktioner, reflecting that more than one primary capability is essential for operation, such as an integrated platform that supports data processing and communication. Related terms include kärnfunktion and primärfunktion, which are used to describe the core function in similar contexts.