Architecture as defined in Brooks' Aristocracy, Democracy, and Systems Design (The Mythical Man-Month)

"By the architecture of a system, I mean the complete and detailed specification of the user interface...The architect of the system, like the architect of a building, is the user's agent. It is his job to bring professional and technical knowledge to bear in the unalloyed interest of the user, as opposed to the interests of the salesman, the fabricator, etc." (45)

I don't know that I've ever seen a system's architecture defined that way before. It seems limiting to think of architecture solely as the user interface, but the idea of the architect as the user's agent is interesting.

"Architecture must be carefully distinguished from implementation. As Blaauw has said, 'Where architecture tells what happens, implementation tells how it is made to happen.' He gives as a simple example a clock, whose architecture consists of the face, the hands, and the winding knob. When a child has learned this architecture, he can tell time as easily from a wristwatch as from a church tower. The implementation, however, and its realization, describe what goes on inside the case--powering by and any of many mechanisms and accuracy control by any of many." (45)

A great example of the difference between architecture and implementation.