System Diagram

Soooo, the example that helped me to understand this diagram better, was the school example. What was that school example?
      Inputs: In a school, inputs are desks, boards, chairs, teachers, students, books etc.
      Throughput (process): This is the education process. Students are educated and they graduate.
      Outputs: The students that graduated, the money they earned.
      Feedback: Actually all outputs are counted as feedback. For instance, the students who graduated, their success and comments are the feedbacks.
According to these feedbacks, our teachers and deans are able to analyze themselves. So it is a cycle, the feedback turns into an input and it continues like this.