   What is a System?
              A system can be defined as a combination of interrelated 
               elements, called subsystems, organized in a logical manner in 
               order to ensure the effective and efficient functioning of the 
               system as a whole. 
              It is a well-organized set of elements that operate together to 
               accomplish a purpose. 
              The word system implies wholeness, completeness and 
               integration of parts to provide optimum performance of a set 
               of components in a time frame.
              Examples of systems include: business systems, 
               manufacturing systems, service systems, information systems, 
               computer-based management information systems among 
               others. 
           INTRODUCTION
             The transformation process of a system consists of three 
              elements namely: input, process and output
             Input gives the system what it needs to be able to 
              operate. Input may vary from matter, energy, human 
              actions to information
             A process transforms the input to output. Processes may 
              involve tasks performed by humans, plants, computers, 
              chemicals and a wide range of other actions.
             Output is the result of the processing of the input. They 
              represent the purpose for which the system exists. Output 
              in one system may be used as input in another system.
          COMPONENTS OF A SYSTEM 
          (TRANSFORMATION PROCESS)
              A system does not exist in a vacuum, rather it exists and 
               functions in an environment containing other systems. 
              The system has connection or relationship with its external 
               environment because Input comes from the environment and 
               outputs are transferred to the environment. 
              The boundary delineates the scope of a system and serves 
               three main purposes which are:
              It encloses the system activities;
              It demarcates the system from other systems in the external 
               environment; and 
              It reflects the system objectives.
           SYSTEM ENVIRONMENT AND 
           SYSTEM BOUNDARY
             A system is not complete without feedback and control 
              mechanisms. 
             Feedback is the modification or control of a process or 
              system by its results or effects, by measuring differences 
              between desired and actual results. 
             Feedback is the data about the performance of a system. 
             Control involves monitoring and evaluating feedback to 
              determine whether a system is moving toward the 
              achievement of its goal. 
             The control function causes necessary adjustment to a 
              system’s input and processing components to ensure 
              that it produces proper output. 
          FEEDBACK AND CONTROL 
              Open System
           An open system is a system which interacts with its environment 
           for collection of input. This input may be information on business 
           transaction with suppliers, customers, the general publics, 
           government departments, trade organizations etc. 
           A business is an example of an open system
              Closed System
           This type of system does not interact with its environment either 
           for the exchange of information or business transaction. It 
           neither has input nor output. It is isolated from the external 
           environment and independent of it. 
           Example is some scientific systems like insulated container or 
           the operation of a thermostat.
           TYPES OF SYSTEMS