The system life cycle model is defined as the framework containing the processes, activities, and tasks involved in the
development, operation, and support of a system.
The word “cycle” in the above definition refers to the way a system usually evolves through several cycles of development and enhancement during its life span
The concept of a development process model discussed next is an important part of the system life cycle model. It covers the activities and tasks starting from the definition of requirements to the deployment of the developed system.
The system concepts are established by capturing the user needs or requirements, and defining the scope of the system. This phase produces documents with titles such as “The Mission Needs Statement”, “The Operational Requirements”, or “The User Requirements Document”.
Capturing the user requirements involves the following:
• Concept exploration,
• The use of documented experiences with other systems,
• The use of specially developed prototypes, and