3. Software engineering life cycle

3.1 Notion of life cycle

Software is a complex entity, and its development requires a diversity of activities. An effective technique for managing the complexity of a whole is to subdivide it into several parts. It is therefore essential to structure the approach to software quality.

What's more, representing the real world implies a process of abstraction that leads to the use of a model. Thus, modeling, or the reduction of the real world, introduces the notion of successive activities, hence the concept of "life cycle". This modeling is doubly useful:

• it provides a graphic and logical representation;

• it provides a structure around which quality assurance activities can be built...