Introduction to Information System (IS)

Information system is an integrated set of components for collecting,  storing, knowledge,  processing data for delivering information, and digital products. Business firms and other organizations rely on information systems to carry out and manage their operations, interact with their customers and suppliers, and compete in the marketplace.  To reach their potential customers with targeted messages over the Web, to process financial accounts, and to manage their human resources corporations use information systems. Governments deploy information systems to provide services cost-effectively to citizens. Digital goods such as electronic books  and software, and online services, such as auctions and social networking, are delivered with information systems. Individuals rely on information systems, generally Interner-based, for conducting much of their personal lives: for socializing, study, shopping, banking, and entertainment.

The 5 components  in  a computer-based information system:

1. Hardware
The hardware refers to machinery. This category includes the computer, which is often referred to as the central processing unit (CPU), and all of its support equipments.There are input and output devices, storage devices and communications devices among the support equipments.

2. Software
Software refers to computer programs and the manuals that support them. Computer programs within the hardware parts of the system are machine-readable instructions that direct the circuitry to function in ways that produce useful information from data. Programs are generally stored on some input / output medium, often a disk or tape.

3. Data
 Data are facts to produce useful information facts that are used by programs. Like programs, data are generally stored in machine-readable form on disk, pendrive or tape until the computer needs them.

4. Procedures  

Procedures are the policies that govern the operation of a computer system. The common analogy used to illustrate the role of procedures in a system is "Procedures are to people what software is to hardware".

5. People
 If it is to be useful, every system needs people. Probably the component that most influence the success or failure of information systems is people which is often the most over-looked element of the system.

Types of Information System

1. Transaction Processing Systems

Transaction processing System is an information system that captures and processes generated data during day-to-day transactions in an organization.  A transaction is a business activity such as a deposit, payment, order and reservation.

2. Office Support System

An information system that uses hardware, software and networks to facilitate communications among employees and enhance work flow. Office information system, or also known as office automation is an employees perform tasks electronically using computers and other electronic devices, instead of manually.  With an office support system, for example, a registration department might post the class schedule on the Internet and e-mail students when the schedule is updated.  In a manual system, the registration department would mail the schedule to each student’s  house after making the photocopy.

 3. Management Information Systems

 Managers soon realized that the computers’ capability of performing rapid calculations and data comparisons could produce meaningful information for management after a while using  computers as ideal routine transaction processing.  Management information systems then evolved out of transaction processing systems.  A management information system, or MIS , is an information system that generates accurate, timely and organized information so managers and other users can make decisions, solve problems, supervise activities, and track progress and sometimes is called a management reporting system (MRS) as it generates reports on a regular basis.

4. Decision Support Systems

When a decision-making situation arises, an information system designed to help users reach a decision.  A variety of DSSs exist to help with a range of decisions. 

5. Executive Information System

For those who have less expertise, information system captures and stores the knowledge of human experts and then imitates human reasoning and decision-making processes.  Executive information systems are composed of two main components: 

1)  a knowledge base

·       A knowledge base is the combined subject knowledge and experiences of the human experts.

2)   inference rules 

·       The inference rules are a set of logical judgments applied to the knowledge base each time a user describes a situation to the expert system.