Definition of System
I will talking about basic concept of the system. If we are discuses about system, this have two approach to attach the meaning of that. There are from his procedure and at component or element that his arrange. Looked from procedure, system is a work networks from procedures that interactions, do something work together or to completing something goal from the system. But, if we use approach element that his arrange, system is a set of elements that interactions for gain something goals.
Characteristic of System
System have some certain characteristic such as components, boundary, environments. Interface. Input, output, process and objectives or goal.
System is consist a set of components interactions
Boundary will show scope of the system and bordering this system from other system or their environments.
Everything is out of system called by environment. Environment may good and bad effect to the system.
Interface connect between subsystem to other subsystem on the system.
Input is all energy’s input to the system. There are two kind of input that is maintenance input and signal input.
Output is result from energy’s processed and classified be output useful.
Goal or Objectives
Classification of System
We can classifying the system from some point of view, there are :
System is classified as abstract system and physical system
Abstract system refer to a system that can’t see uses sense-organ because originate from idea, like teology, culture. And physical system form of physical like computer system, machine system, etc.
System is classified as natural system and human made system
Sample from natural system like the earth rotation system, etc. and human made system like information system.
System is classified as deterministic system and probabilistic system
Deterministic system like computer system, because output of this system is predictable, while probabilistic system is unpredictable.
System is classified as closed system and open system
Closed system is system which not connected by out side environment. And Open system is a system connected and influence from out side environment. This system accept input and generate output it will forward to out side environment and their subsystem.
Basic Concept of Information
Information is very important for organization, because information will determining of policy of company. Before we are talking about information, we have to know about different between data and information. Data refer to a collection of facts usually collected as the result of experience, observation or experiment, or processes within a computer system, or a set of premises. This may consist of numbers, words, or images, particularly as measurements or observations of a set of variables. And, information is data have been processed and be something that useful for recipient. From that statement we can conclude that data is source from information.
I will give you example for more understanding about cycle above. In activity of a company usually there are some data have been created. This data will be input to the system and will be processing. As the explain above, the information will be output from data after processed. This information will be response by user and next user give action for this information. Result from this action is new data system and become new data input for this system.
Quality and Value of Information
Quality of Information dependent of three case such as, accurate, timeliness, and relevance. Accurate mean information must free from change. Information also must accepted by recipient (timeliness) and have benefit for the users (relevance). Value of information is determined by two case, benefit and cost. Information have high value if benefit of this information more than cost for discover.
refference : Jogiyanto, Analisis dan Desain Sistem Informasi, 1991