Architecture

Models are complete, consistent representations of the system to be built. The models of complex systems can be very large.

Suppose you are given the task of describing a system so that designers, programmers, users, and managers would be able to do the following:

• Understand what the system does

• Understand how the system works

• Be able to work on one piece of the system

• Extend the system

• Reuse part of the system to build another one

Now assume that you are given a limited amount of space for this task (for example, a maximum of 60 pages). What you would end up with is a description of the architecture of the system. As someone once told me, "Architecture is what remains when you cannot take away any more things and still understand the system and explain how it works."