Systems engineering is an interdisciplinary approach and means to enable the realization of successful systems. Successful systems must satisfy the needs of its customers, users and other stakeholders. Some key elements of systems engineering include:
• The principles and concepts that characterize a system, where a system is an interacting combination of system elements to accomplish a defined objective(s).
The system interacts with its environment that may include other systems, users, and the natural environment. The system elements that compose the system may include hardware, software, firmware, people, information, techniques, facilities, services, and other support elements.
• A systems engineer is a person or role who supports this interdisciplinary approach. In particular, the systems engineer often serves to elicit and translate customer needs into specifications that can be realized by the system development team.
• In order to help realize successful systems, the systems engineer supports a set of life cycle processes beginning early in conceptual design and continuing throughout the life cycle of the system through its manufacture, deployment, use and disposal. The systems engineer must analyze, specify, design, and verify the system to ensure that its functional, interface, performance, physical, and other quality characteristics, and cost are balanced to meet the needs of the system. • A system engineer helps ensure the elements of the system fit together to accomplish the objectives of the whole, and ultimately satisfy the needs of the customers and other stakeholders who will acquire and use the system. Systems and Systems Engineering When we speak of a “system,” we may mean an engineered system, a natural system, a social system, or all three. Since the province of Systems Engineering (SE) is engineered systems, most SE literature assumes that this is the context. Thus, in an SE discussion, “system architecture” would refer to the architecture of the system being engineered (e.g., a spacecraft) and not the architecture of a natural system outside its boundary (e.g., the solar system). This may produce ambiguities at times: for example, does “management” refer to management of the SE process, or management of the system being engineered?
In such cases, the SEBoK tries to avoid misinterpretation by elaborating the alternatives into “system management” or “systems engineering management.” As with many special disciplines, SE uses terms in ways that may be unfamiliar outside the discipline. For example, in systems science and therefore SE, “open” means that a system is able to interact with its environment--as opposed to being "closed” to its environment. But in the broader engineering world we would read “open” to mean “non-proprietary” or “publicly agreed upon.” Some special meanings or terms reflect the historical evolution of SE. “Systems architecting” was introduced in (Rechtin 1991) to embody the idea that better systems resulted from concurrently rather than sequentially addressing a system’s operational concept, requirements, structure, plans, and economics. “Soft SE” was introduced in (Checkland 1981) to express the criticality of human factors in SE. In both cases, the emphases that these terms imply are now accepted as integral to SE.