TABLE OF CONTENTS better to understand a little, than to misunderstand a lot
Homer Simpson
This section introduces the concept of modelling and includes a discussion on why modelling is so important and why we need to model. It also contains information that forms the basis for the remainder of this part of the book and introduces a number of basic concepts that will be referred to constantly throughout the rest of the book.
It is vital to understand the reasons why we must model things. In order to justify the need for models, it is probably easiest to look at a number of simple examples, based on real-world systems, to which people can relate.
Note that here we are justifying modelling in general terms and not simply with regard to software systems, which demonstrates the need for flexibility when modelling - indeed, the three examples used here are nonsoftware systems. Many examples are used in different books, but the examples used here are based on those defined by the master of modelling, Grady Booch [1]. There seems little point in contriving a new modelling example when there is a perfect set of examples that has already been defined and is widely accepted as the norm. Therefore, the examples chosen here are based on Booch and his doghouse, house and office block.
For the first example of modelling, consider the example of building a kennel. A kennel is a small...
