Before studying what that Information Systems Analysis and Design, first we have to know what that system and what that information.
A.WHAT IS SYSTEM?
There are two approaching to definition of system:
1. Definition of system based on approach of procedure
According to this approach, system interpreted by as a working network from procedures which is interaction and work along to finish a specific-purpose or goal. A procedure is a correct sequences of instruction steps explaining what have to be done, who have to do, when have to be done and how to do that.
2. Definition of system based on approach of element
According to this approach the definition of system is a set of elements which is have interaction to reach specific-purpose or goal.
B.CHARACTERISTIC OF SYSTEM
• Components of system
The component of system is consist of a number of subsystem. One of system can have a big system that mention supra system.
• Bounds of System
Bounds of System defines difference between the environment and the system.
• Environment
The environment represents everything that is important to understand the function of the system, but is not part of the system. The environment can be ignored in the analysis except for its interaction with the system. It includes: competition, people, technology, capital, raw materials, data, regulation and opportunities.
• Interface
Interface is the media which connect one of sub system with other sub system.
• Input
Input means all of resources that entered into the system
• Output
Output is result of input had been processed.
• Process
Process means change input to be output
• Goal and objective
Goal and objective means what for the system have been created and whose for the system have been created.
The Classification Of System
a. Deterministic System
The Certain system operate with behaviour which have earned can be predicted, interaction between its sharess can be detected categorically so that its output can be forecasted. for example of : Computer programe, executing precisely as according to its instruction network. System of pay, and others.
b. Probabilistic System
The System which is input and its process can be defined, but yielded output cannot be determined categorically; ( always there is a little mistake / deviation to forecast of the way system). for Example : marketing system)
c. Open System
The system that relation and effect external environment .This system accept input and yield output for external environment / the other sub system, so that have good operation system. This system tend to measure up to adaptation, can adapt to its environment so that can continue its.
d. Closed System
The System Physical where the process that happened do not experience of transfer of items, information or energy with environment outside system. This system work automatically without existence of interfere in of external side of it.
e. Relatively Closed System
The closed System but doesn't closed at all to accept other influences. This system in its operation can accept influence from outside which have been defined in certain boundarys.
f. Artificial System
The System imitating occurence in system. This system is formed pursuant to occurence in nature where human being unable to do it. Equally imitat exist in nature.
g. Natural System
The natural System is occurence in nature. for Example of : sea, solar system and others.
h. Manned System
The System explanations of behaviour covering human being taking part in. This system can be depicted in way of as follows:
The System of Human being focus the relations between human being
The System of Human being - Machine, System which involve machine to a target
The Machine System, automatic system where human being have duty to start and finish system, meanwhile human being entangled also to monitor system.
C.Information
Data is fact. Information is data that processed become better form and more meaning to accept it. If data is not useful to accept it so the data cannot be referred as by information.
QUALITY OF INFORMATION
To get information with quality, then information must have:
* Accurately
Information free from mistakes and doesn't deflect or mislead
* Punctually
Incoming information at receiver may not lose time
* Relevantly
Information is have benefit for its usage.
Information will be valuable if big added significance of expense get it
Value of Information
Information does not have an absolute universal value, but we can say the information have a value if the use of information more effective than the cost to have it.
Information System
After we describe the definition of system and information, then we can define the definition of information system. An information system can defined technically as a set interrelated components that collect, process, store and distribute information to support decision making and control in an organization.
Three activities in information system produce the information organizations need for making decision, controlling operation, and output.
• Input
Input capture are collect raw data from with in the organization or from its external environment.
• Processing
Processing converts this raw input into a more meaningful form.
• Output
Output transfer the processed information to the people are activities where it will used. Information system also requires feedback, which is output that is returned to appropriate members of the organization to help them evaluate or correct the input stage.
