Before giving a definition of the concept of information system, we will begin by defining the terms that what constitute: System and information. The word system is now used in many different areas: refers to electrical systems, monetary systems, security systems, the solar system and, even, game systems in football teams. The reason is that, as it happens with other words as a whole, the term system is used to designate a concept, a generic tool that can be used to explain or analyze better is like or what happens in a particular area of social, economic, physical, etc. The dictionary of the Spanish Royal Academy says that system is a set of things that orderly interrelated contribute to a particular target. From this definition, we can identify what are the main elements in any system: the components of the system. The relationships among them, that determine the structure of the system. The objective of the system. In any type of system can identify these elements.
In the circulatory system of the human being can determine its constituent bodies (heart, arteries, veins, etc.), the relationships between them (the heart pumps blood into the arteries that are arranged according to a particular structure, etc.) and the objective (ensuring the supply of blood throughout the body). Management of information and knowledge on foundations in all systems can also identify other important elements to understand how they are and how they work: the system environment: that surrounds it, within which it is located. The limits of the system: the border between what is and what constitutes the environment. In the case of the human circulatory system, environment where it is located is the body, and the border is the membrane or the limit of each of their bodies with the rest of the body that does not belong to the system. They also exist relations between the system or its components and abroad represented by the environment (System nervous sends orders to the heart or to modify their heartbeats).