Domäne

Domæne is the Danish term for domain and is used across many disciplines to denote a defined area, space, or scope. In general, a domæne identifies the set of things that are governed by a particular rule, function, or context.

In mathematics, the domain of a function is the set of all input values for which the function is defined. The domain is paired with a codomain, and the actual output values form the range. The domain may be restricted to ensure the function is well-defined, for example when avoiding undefined expressions.

In computing and networking, a domain can refer to a domain name system (DNS) domain, a hierarchical naming space used to identify resources on the Internet or a local network. It can also denote a Windows domain, a collection of computers and user accounts managed under common security policies, enabling centralized authentication and administration.

In biology, a protein domain is a distinct structural or functional unit within a protein that can fold independently and often carries a specific activity. The concept of domains supports the modular view of protein architecture and evolution.

In law and governance, domain can describe a jurisdiction or area of responsibility—such as the sovereign domain of a state or the domain of competence of a public institution. The term is also used more broadly to indicate an area of influence or activity, such as a cultural or research domain.

In linguistics and logic, domain is used to refer to the domain of discourse or the range of values over which variables or quantifiers operate.