
Although the term architecture was introduced only ten years ago in computer technology (Buchholz), the concept of architecture is as old as the use of mechanism by man. When a child is taught to look at a clock, it is taught the architecture of the clock. It is told to observe the position of the short and the long hand and to relate these to the hours and the minutes. Once it can distinguish the architecture from the visual appearance, it can tell time as easily from a wrist watch as from the clock on the church tower.
The inner structure of a system is not considered by the architecture: we do not need to know what makes the clock tick, to know what time it is. This inner structure, considered from a logical point of view, will be called the implementation, and its physical embodiment the realisation.
Source: Computer architecture (1972), p. 154