Submitted To: Rutvi sarang

Submitted By: Kushal Bhagat

At present, computer have become an essential part of organizational information processing, because of the power of the technology and the volume of data to be processed. Today, computerized processing of transaction data is to use the capabilities of computer to support knowledge work, including managerial transaction processing to provide for a formal information and reporting system and to accomplish managerial decision support are broadly classified as the ‘organisation management information system’.

1) System description

2) Input documentation

3) Output documentation

4) File design

5) Program logic

6) Computer program

7) System verification

8) Documenting

System descriptionIt is usually prepared after preliminary investigation and definition of the problem. The description is essentially a statement of the major inputs, outputs, processing operation and files needed. The purpose is to show the logical flow of information and logical operation necessary to carry out the particular design alternatives chosen. These are in both narrative and pictorial form.

Narrative: The narrative description is an English language depiction of the operation. It should describe inputs, outputs, files and operation. It should be of that detail that will allow users and computer technicians to understand the operation of the system

Pictorial: A picture allow us to condense greatly the narrative version of our system description. There are number of method of depicting system production, ‘flow charting’ is one of the most popular techniques of use even today. System flow chart is a graphic diagramming tool used to show the flow of data media as they are processes by hardware device and information processing procedure in an information system.

coffee Tea

White Black WhiteBlack

No Yes

start

Which drink

Black or

White

Black or

White

Fill cup with milk or coffee

Fill cup with

co0ffee

Fill cup with milk

or tea

Fill cup with tea

sugar

Stir drinkStop

Add sugar

Input documentation: It is necessary to specify how the information will be put into a form that is acceptable to the computer. Volume of information, frequency, accuracy and verification requirement, and the handling of the information are the consideration in the selection of inputs formats. The exact layout of input documentation is necessary because the computer program is an exact and precise sequence of steps that operate only when data are located in prescribed position.

Output documentation: The output format should be treated with additional care since it represents the purpose or objective of the entire operation. It is the output and hence the management is more concerned because of its critical nature. Hence, care should be taken in its design.

File design: The logic required to control the flow of data through the system design, and the flow is in turn dependent of the design of data files. These two steps are closely associated and should be considered in conjunction with consideration of type of equipment, storage capacity, input and output media and format

Program logic: There are numerous means of thinking through documenting program logic. Flow charts are historically dominants; easy to depict and understand. The program flow chart is the programmer’s logic of the detailed, step by step representation of how the computer program will accomplish the job.

process

Input/output

Decision

extract

Merge

Connector

Online storage

Sort

Flow chart symbols

Computer programming: We are concerned only with the general nature of how the processor is instructed to perform its operation on the input data to produce output data in the desired format. In simplified form, an instruction to the processor consists of two parts.

1) An operation code , 2) operands

System verification: After the program has been written and run through the compilation process, it is placed in memory in binary or ‘machine readable’ form and is ready to process the terminal input, update the master file in disk and print the required report. The computer will execute the instruction of the program in sequence, until the program comes to a halt. The possibilities of all programs working correctly for the first time approaches zero. Test cases must be run against each program and all errors corrected

Documentation: More system fails for lack of adequate documentation than for any other single reason. Three types of documentation needed are:• For input, a simple overview of the system, a clear description of what exactly input is expected and a about what input is not acceptable.• For running and maintaining the system, all the technical documentation generated during the development process.• For output, a simple overview of the system, a clear description of what the output means and a note about its limitation. 

Types of information system

Information system

Operating support systems

Management support systems

Transaction

processing

systems

Enterprise collaborati

on systems

Process control systems

Execution

information

systems

Management

information systems

Decision support systems