"Systems Engineering for the rest of us..."
We have all seen models and have a fairly intuitive idea of what they are. Some of the most familiar are the model cars, dolls, houses and planes we had as children. These really are the same idea approached from a different perspective. where one has a predictable logical explanatory value and the other is more emotional.
A model is a representation of reality or intended reality that has only the attributes necessary to solve a class of problems. For example; a model airplane is usually a shell that shows us what the plane looks like on the outside or performs in a wind tunnel but has no internal features or other functional characteristics.
Models can be physical or logical (informational). Information models capture aspects of a system called attributes. An information model of balls might contain the attributes diameter, purpose, pattern, color etc.