What exactly is a system? A system is set of interconnected components or networks; the system has the ability to maintain itself through a series of feedback loops. What the hell does the mean? The easiest way to explain what a system is, is through the use of an example. Think of music. If thought of a in a linear point of view, it’s basically listen to and discarded when it is no longer useful. From a systems perspective, music from the past inspires music from the future. There is no waste; regardless of whether the music discarded by users was good or bad it allows future generations of musicians to learn from it.
The text talks about the different components of a system, the stock and the flow being the most fundamental. In simple words, the stock is the stuff that goes into the system (can be tangible or intangible). The stock constantly changes over time based on the flow. The system is said to run itself through the use of what is called a feedback loop. The feedback loop is the corrective actions taken to main the system.