SYSTEM Derived from Greek word Systema. Means an organised relationship among functional units or components. A group of interdependent items that interact regularly to perform a task. A computer system refers to the hardware and software components that run a computer or computers.
Definition A system is an orderly grouping of interdependent components linked together according to a plan to achieve a specific objective. System has 3 basic implications- A predetermined objective- Interelationship and interdependence among the components.- Objectives of the organisation have a higher priority than that of components.
Characteristics of a system Organised : Well structured arrangement of components Interaction:Manner in which each component interact with each other Interdependence:Dependence of one subsystem on one or more subsystems Integration: Functional integrity of the subcomponents and the system as a whole Central Objective:Goal of the organization
Elements of a system• Inputs and Outputs• Constraint• Processors• Control• Feedback• Environment• Boundaries and Interface
Types of System A dynamic system is a system that is constantly changing, like the human body system. A static system is a system in which there is no change, like the solar system. Dynamic systems tend to become static or attain a state of equilibrium. e.g. if a car is assumed to be a dynamic system, then it requires fuel to continue moving forward or else it would come to a stop and become static.
Open Systems Interaction across boundaries Recieves and delivers input and output to the outside world. Adapts the changing demands of the user.
Characteristics of open systems• Input from outside• Entropy Process output to outside world Equifinality
CLOSED SYSTEMIsolated from environmental influencesCompletely closed system is rare
Logical and Physical system descriptionLogical system descriptionDescription of a system that focuses on the system function and purpose without regard to how the system will physically implementedPhysical system descriptionDescription of a system that focuses on the how the system will be materially constructed
INFORMATION SYSTEMSInformation system is an organised combination of people, hardware,software, communication, networks and data resources that collects, transforms and disseminates information in an organisation.
COMPONENTS OF INFORMATION SYSTEMS DATA PEOPLE HARDWARE SOFTWARE NETWORKS
TYPES OF INFORMATION SYSTEMFORMAL INFORMATION SYSTEMINFORMAL INFORMATION SYSTEMCOMPUTER BASED INFORMATION SYSTEM
FORMAL INFORMATION SYSTEMBased on an organisation chartThere will be a pattern of authority,communication and work flow.Information is in the form of reports,instructions, memos.
INFORMAL INFORMATION SYSTEM• Designed to achieve company goal• Employee based system
COMPUTER BASED SYSTEMDepends on computer system for business handling and problem solvingStructured problem -Definite format, definite solution
ROLE OF INFORMATION SYSTEMSupport of business operationsSupport of managerial decision makingSupport of Strategic competitive advantage
INFORMATION SYSTEM ACTIVITIESInput of data resources Data entry activities Recording and editing of dataProcessing of data into information Calculating, comparing, sorting, classifying, summarizingOutput of information products In the form of messages,reports,forms, graphs etc
Storage of data resources Basic system component of information systems. Stored data in the form of records, files databases .Control of System performance Monitoring and evaluating the feedback.