Overview of Systems
A system is a set of elements or components that interacts to accomplish goals. The elements themselves and the relationship among them determine how the system works (Stair and Reynolds 2008). The elements and components are individual parts that work together as one entity to achieve a particular goal of that entity. A good example of a system is a typical manufacturing company that consists of people grouped into different departments such as production unit, packaging unit, sales and distribution unit and marketing unit. All these unit forms part of the elements and components of the company and ensure that the general objective or goal of the company which is to manufacture a product and sell it to customers is achieved. The human body is also a good example of a biological system. The head, hand, legs, digestive, respiratory and excretory systems are all elements that work together to keep the whole human body alive. According to D. V Tesone (2006), the elements or components can be complete systems on their own, and the whole entity can also be a subsystem in relation to a larger system. For example, in the human body example given above, the digestive system, which is a component of the human body, is a complete system on its own, which has individual elements such as intestines, food and digestive enzymes. The whole human being, which is an entity on its own, can also be part of a larger system called the human family system.
Characteristics of systems
Terry Lucey (2005) identified five important characteristics of systems. Firstly, all systems are composed of interrelated parts or sub-systems and the systems can only be explained as a whole. Secondly, systems are hierarchical in that the parts of sub-systems are made up of other smaller parts. Thirdly, the parts of a system cannot be altered without affecting other parts. Also, the sub-systems should work towards the goal of their higher systems and not pursue their own objectives independently. Lastly, systems contain both hard and soft properties. Hard properties are those that can be assessed in some objective way. Soft aspects on the other hand cannot be assessed by any objective standard or measuring process.
Components of a System
All systems are composed of the same basic components. Stair and Reynolds (2008) identified them as inputs, processing mechanism, output and feedback. To understand the various components of a system, this example concerning an automatic car washing system will help. Inputs for the process are a dirty car, water, and various cleaning ingredients. Time, energy, skills and knowledge also serve as input to the system because they are needed to operate it. The processing mechanism involves the actual cleaning and drying of the car. The output is a clean car and the feedback mechanism is the assessment of how clean the car is by the owner. Whether the owner of the car appreciates the work done by the system or not.
Types of Systems
Systems are generally classified into two types. They are open and closed systems. According to Terry Lucey (2005), an open system is a system that interacts with its environment. It receives inputs and influences from the environment and, in turn, passes back outputs and influences to the environment. All social organizations are open systems. The way these organizations adapt to changes in the environment is the key element in the organizations success. Organizations that are open systems attempt to monitor and anticipate environmental disturbances. However, some disturbances are so great or unexpected that the existence of the organization it threatened. Some of this disturbances may arise from virtually any source which may include changes in market conditions, technology, the law, conflict and so on. A closed system on the other hand, is one that is isolated from its environment. Closed systems are self-contained so that the external environment does not influence the behavior of the system, nor does the system influence its environment. An example of this is the production sub-system of an organization where arrangements are usually made to limit exchanges with the external environment so that operations can flow as smoothly as possible. The production control system, the sales and distribution system, the human resources system and so on act as buffers between production and the outside world.
However, D. V Tesone (2006) argues that the two traditional types of systems are too broad and that, they are based only on their interactions with the environment without considering other factors such as the life span of the system. Hence, he provided two other types of systems in addition to the traditional open and closed systems, which he termed mechanic systems and organic systems. He explained mechanic systems as closed systems with definitive life spans and continuously atrophy into nonexistence. For example, a computer, for instance, will eventually break down and stop working when it exhaust its life span. It does not have the capacity to evolve. On the other hand, organic systems have the capacity for infinite life because of their ability to evolve. For instance, a biological plant or animal will generate offspring during its lifetime and will feed the earth after the end of its biological life.