Information Systems Development

By now, we have gained an understanding of what information systems are and also seen their importance within an organisation. In this section, we discuss how information systems are developed. Developing information systems is a complex process (especially large-scale information systems). There have been many attempts in developing information systems that have failed to meet their objectives. Hence, information system development has been extensively studied and many approaches are proposed for information system development. We will study the traditional System Development Life Cycle approach, which is also known as the Classical Life Cycle Model, Linear Sequential Model or the Water Fall Model. There are other approaches such as Prototyping Model, Rapid Application Model, and so on, which are not discussed and beyond the scope of this textbook. All these approaches have advantages and disadvantages and selecting the appropriate model for system being developed is important. Certain IT organisations have created their own system development methodology by borrowing concepts from different models.

Effective systems development requires a team effort. This team consists of users, managers, systems development specialists and various support personnel (i.e. stakeholders). Stakeholders are individuals who, either themselves or through the area of the organisation they represent, ultimately benefit from the systems development process. Depending on the project, the development team may include a systems analyst. A systems analyst is a professional who specialises in analysing and designing business systems. Systems analyst plays various roles while interacting with the stakeholders (users, management, vendors and suppliers, external companies and suppliers, software programmers and other support personnel). Like an architect that builds the blueprint (also known as plan) for a new building, a systems analyst develops detailed plans for the new or modified system.

The System Analyst plays an important role in the development team and
is often the only person who sees the system in totality

The System Life Cycle

Similar to humans, plants and animals, information systems also have a life cycle. An information system also follows a system life cycle – from its development to operation and to final retirement. The system life cycle divides the life of an information system into two stages as follows:

• System development: developing the information system

• Systems operation and support: running the system and supporting it until its retirement.

A system development methodology implements the development stage of the system life cycle. Next, we will study the trad itional System Development Life Cycle methodology.