SAD(SYSTEM ANALYSIS AND DESIGN)
Before study about SAD its important to know about SYSTEM
WHAT IS SYSTEM
The word “System” is derived from a Greek word ‘Systema’ which means an organized relationship among functioning units or components.
A system is an orderly grouping of interdependent components linked together according to a plan to achieve a specific purpose.
From the above definition it is clear that .
• System is a group of components
• The components are interdependent
• The components are linked together to achieve a specific purpose.
A business organization is a system with its components as:
ELEMENTS OF SYSTEM
7. Boundaries and Interfaces
• A system must be capable of producing an output that must be of value to the user. Whatever be the nature of the output (goods, services, or information) , it must be in accordance or inline with the user’s expectations. Output is the outcome of a processing.
• Inputs are the elements that enter the system for processing. The essential characteristics of the input are:,/
a. Accuracy: If the data is not accurate, the output will be inaccurate/wrong.
b. Proper format: The input must be in a proper format.
c. Timeliness: If the data is not available at the time, the whole system may fail.
d. Economical: It is required that the data must be produced at a low cost.
• It is the operational component of a system. This involves the programs and the way in which data is processed through the computer. This element of the system involves the actual transformation of input to output. It may modify/transform the input totally or partially as per the requirement.
• This element is needed to control all the activities governing/concerning input, processing and producing the output. The system is always guided by control. In an organization, management as a decision making body controls the following activities of the organization:
• It refers to the external elements that effect on the system. It determines how a system must function. The environment consisting of vendors, competitors and others may influence the actual performance of a business system. Thus, a system must be capable enough to adjust with its environment. It should change according to the changing environment.
• The information supplied by comparing results with standard and informing the control elements about the differences is termed as “Feedback”. It is a way to measure/compare output against a standard.
• Feedback may be positive or negative. Positive feedback reinforces the system performance. Negative feedback provides information for an action. Thus feedback is an important element of systems.
7. Boundaries and Interfaces:
• The limits of a system are specified by its boundaries. Every system has defined boundaries within which it operates. It enables to know which element lie or do not lie within the system. The limits or boundaries of a system to identify its components, processes and interrelationships when it interfaces with another system.