Systems development is systematic process which includes phases such as planning, analysis, design, deployment, and maintenance. Here, in this course, we will primarily focus on −
It is a process of collecting and interpreting facts, identifying the problems, and decomposition of a system into its components.
System analysis is conducted for the purpose of studying a system or its parts in order to identify its objectives. It is a problem solving technique that improves the system and ensures that all the components of the system work efficiently to accomplish their purpose.
Analysis specifies what the system should do.
Systems Design
It is a process of planning a new business system or replacing an existing system by defining its components or modules to satisfy the specific requirements. Before planning, you need to understand the old system thoroughly and determine how computers can best be used in order to operate efficiently.
System Design focuses on how to accomplish the objective of the system.
System Analysis and Design (SAD) mainly focuses on −
Systems
Processes
Technology
What is a System?
The word System is derived from Greek word Systema, which means an organized relationship between any set of components to achieve some common cause or objective.
A system is “an orderly grouping of interdependent components linked together according to a plan to achieve a specific goal.”
Constraints of a System
A system must have three basic constraints −
A system must have some structure and behavior which is designed to achieve a predefined objective.
Interconnectivity and interdependence must exist among the system components.
The objectives of the organization have a higher priority than the objectives of its subsystems.
For example, traffic management system, payroll system, automatic library system, human resources information system.
Man-made information systems are divided into three types −
Formal Information System − It is based on the flow of information in the form of memos, instructions, etc., from top level to lower levels of management.
Informal Information System − This is employee based system which solves the day to day work related problems.
Computer Based System − This system is directly dependent on the computer for managing business applications. For example, automatic library system, railway reservation system, banking system, etc.
Systems Models
Schematic Models
Flow System Models
Static System Models
Dynamic System Models
Business organizations are dynamic systems. A dynamic model approximates the type of organization or application that analysts deal with.
It shows an ongoing, constantly changing status of the system. It consists of −
