This document discusses concepts, constructs, and conceptual systems. It defines a concept as a generic idea or thought developed from experiences that are used to make sense of the world. Concepts are the building blocks of thinking. Constructs refer to higher order concepts that group concepts together at a higher level of abstraction. Variables are a type of construct that have different levels or values. Conceptual systems link concepts together to represent relationships and provide understanding of reality by identifying, organizing, and explaining phenomena. The goal of conceptual systems is to achieve understanding to satisfy goals of satisfaction and control.