Glossary Category:


A Requirement specifies a System (Element)’s desired characteristic, quality, function aspect or behavior in defined circumstances under specific  conditions.

⌊Requirements Engineering⌋

The purpose of Requirements Engineering is

  • To establish a complete set of stakeholder needs and
  • ensure the correct and complete transition from stakeholder needs via product design to the implementation level, without loss of information (content and intent), during the product or service decomposition steps in the development process.

⌊System (INCOSE)⌋

An integrated set of elements, subsystems, or assemblies that accomplish a defined objective. These elements include products (hardware, software, firmware), processes, people, information, techniques, facilities, services and other support elements. ⌊INCOSE 2015⌋

⌊System (NASA)⌋

A “system” is the combination of elements that function together
to produce the capability required to meet a need.
The elements include all hardware, software, equipment, facilities, personnel, processes, and procedures needed for this purpose; that is, all things required to produce system-level results.