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Unit 1: Introduction to Information System Development

1.3.1 System Notes

The term system is derived from the Greek word systems, which means an organized relationship
among functioning unit’s or components. A system exists because it is designed to achieve one
or more objectives.
A system is a set of interrelated elements that collectively work together to achieve some goal.
For instance, accounting is a system with elements, viz., journals, ledgers, people, etc. and its
basic goal is to maintain book of accounts along with preparation of financial and MIS statements.
Computer is also a system with elements such as CPU (Central Processing Unit), input device,
output device and users; and its basic goal is to process the data and provide information. There
are hundreds of definitions of the word ‘System’, but here we define it as follows:
A system is a set of interrelated elements that form an activity or a processing procedure in order to achieve
a common goal or goals by operating on data to yield information.

1.3.2 Subsystems

Most systems are part of a larger system. For instance, Financial Accounting System, Marketing
System, and HRD (Human Resource Development) System are parts of a larger system, MIS
(Management Information System) and are called subsystems. A system can be made up of
many subsystems. A subsystem is defined as follows:
A subsystem is that part of a system that carries one part of the system function.

1.3.3 System Study

Systems study may be defined as “a study of the operations of a set of connected elements and of
the interconnections between these elements”. It shows clearly that one cannot ignore any part
or element of a system without first finding out the effect that element has on the operation of
the system as a whole. We can understand this with the help of systems analysis.

1.3.4 System Approach

The information systems (such as MIS) are designed on the basis of synergy of subsystems (such
as Production, Inventory, Sales and Marketing systems) in order to achieve a net unified cohesive
system.
The approach in developing information systems involves focus on the design of a whole
integrated system rather than on independent subsystems in order to optimize the net results of
the operations of an organization. This is called the systems approach.

Example: An invoicing system, an inventory control system and a financial accounting
system can be designed independently. However, the net results of the operations of an integrated
whole system are more than that of independent subsystems.

1.3.5 Difference between System Approach and System Analysis

There is a difference between “systems approach” and “systems analysis” also. The systems approach
shows a set of procedure for solving a particular problem. It applies scientific methods to observe,
clarify, identify and solve a problem with special care being taken to understand the inter-relatedness
between elements and their system characteristics. However, systems analysis is a management
technique which helps us in designing a new system or improving an existing system.

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