is the one in which symbols and logic constitute the model. The symbolism used can be a language or a mathematical notation. A verbal or written description in English is an abstract model. A mathematical model is described in the "language" of mathematical symbols and is an abstract model. A simulation model is built in terms of [..]

is a “procedure by which an authoritative body gives formal recognition that a body or person is competent to carry out specific tasks.” [International Organization for Standardization]

is the degree of transformational accuracy (verity) or behavioral / representational accuracy (validity).

is the state of an object over an interval of time. An activity starts with an event and ends with another event.

is the one who will actively interact with the system or product (e.g., M&S application) once it is operational and in use. Examples: users of the M&S application, administrators of the M&S application, trainers of the M&S application users.

is an entity engaged in a use case. An actor can be a user (human), model component, submodel, submodel of another submodel, or another model as a whole.

is a system which reacts to changes in its environment.

ActiveX Data Objects