COMPONENTS OF AN INFORMATION SYSTEM

An information system model expresses a fundamental conceptual framework for the major components and activities of information systems.  An information system depends on the resources of people, hardware, software, data, and networks to perform input, processing, output, storage, and control activities that convert data resources into information products.

The information systems model outlined in the text emphasizes four major concepts that can be applied to all types of information systems:

·         People, hardware, software, data, and networks, are the five basic resources of information systems.

·         People resources include end users and IS specialists, hardware resources consist of machines and media, software resources include both programs and procedures, data resources can include data and knowledge bases, and network resources include communications media and networks.

·         Data resources are transformed by information processing activities into a variety of information products for end users.

·         Information processing consists of input, processing, output, storage, and control activities.

INFORMATION SYSTEM RESOURCES

The basic IS model shows that an information system consists of five major resources:

·         People resources

·         Hardware resources

·         Software resources

·         Data resources

·         Network resources

People Resources:     

People are required for the operation of all information systems.  These people resources include end users and IS specialists.

·         End Users (also called users or clients) are people who use an information system or the information it produces.  Most of us are information system end users.  And most end users in business are knowledge workers, that is, people who spend most of their time communicating and collaborating in teams of workgroups and creating, using, and distributing information.

·         IS Specialists are people who develop and operate information systems.  They include system analysts, software developers, system operators, and other managerial, technical, and clerical IS personnel.

Systems analysts – design information systems based on the information requirements of end users.

Software developers – create computer programs based on the specifications of systems analysts.

System operators – monitor and operate large computer systems and networks.

Hardware Resources:

Hardware resources include all physical devices and materials used in information processing.

·         Machines  - physical devices (computers, peripherals, telecommunications networks, etc.)

·         Media        - all tangible objects on which data are recorded (paper, magnetic disks etc.)

Examples of hardware in computer-based information systems are:

·         Computer Systems – which consist of central processing units containing microprocessors, and a variety of interconnected peripheral devices.

·         Computer peripherals – which are devices such as a keyboard or electronic mouse for input of data and commands, a video screen or printer for output of information, and magnetic or optical disks for storage of data resources.

Software Resources:  

Software resources include all sets of information processing instructions. 

·         Program - a set of instructions that causes a computer to perform a particular task.

·         Procedures - set of instructions used by people to complete a task.

Examples of software resources are:

·         System software – such as an operating system program, that controls and supports the operations of a computer system.

·         Application software – are programs that direct processing for a particular use of computers by end users.

·         Procedures – are operating instructions for the people who will use an information system.

Data Resources:

Data constitutes a valuable organizational resource.  Thus, data resources must be managed effectively to benefit all end users in an organization.  The data resources of information systems are typically organized into:

·         Databases - a collection of logically related records or files.  A database consolidates many records previously stored in separate files so that a common pool of data records serves many applications.

·         Knowledge Bases - which hold knowledge in a variety of forms such as facts and rules of inference about various subjects.

Data versus Information.  The word data is the plural of datum, though data is commonly used to represent both singular and plural forms.  The term’s data and information are often used interchangeably.  However, you should make the following distinction:

Data: - are raw facts or observations, typically about physical phenomena or business transactions.  More specifically, data are objective measurements of the attributes (characteristics) of entities, such as people, places, things, and events.

Information: - is processed data, which has been placed in a meaningful and useful context for an end user.  Data is subjected to a “value-added” process (data processing or information processing) where:

·         Its form is aggregated, manipulated, and organized.

·         Its content is analyzed and evaluated

·         It is placed in a proper context for a human user

Network Resources:

Telecommunications networks like the Internet, intranets, and extranets have become essential to the successful electronic business and commerce operations of all types of organizations and their computer-based information systems.  Telecommunications networks consist of computers, communications processors, and other devices interconnected by communications media and controlled by communications software.  The concept of network resources emphasizes that communications networks are a fundamental resource component of all information systems.  Network resources include:

·         Communications media (twisted-pair wire, coaxial cable, fiber-optic cable, and microwave, cellular, and satellite wireless systems.

·         Network support (people, hardware, software, and data resources that directly support the operation and use of a communications network).