Glossary
Engineering the needs and requirements of a complex system

Buyer/customer

A stakeholder who acquires or purchases a product or service from a supplier.

Need

Necessity, constraint, desire experienced and expressed by a user, stakeholder or project owner. What is necessary for the purchaser and justifies the design and realization of the system or product. Needs are generally vague at the start of a project: they must be identified, expressed, clarified and made coherent.

Context

All concrete elements outside the system under study, which have a service-type relationship with it, and/or which exchange matter, energy or information with it, and/or which are physically connected to it.

Requirement

Clarified expression of a need, presented in a formalized (computerized, graphical,...