"Software architecture is a burgeoning field of research and practice within software engineering. Alternatively, to be more precise, the architecture of large, software intensive systems has been the subject of increasing interest for the past decade. What accounts for this surge of interest in a field that, until about 1990 was unheard of? To begin, the field did not spontaneously create itself in 1990. However, that time frame was when the term “software architecture” began to gain widespread acceptance and when the field first attracted substantial attention from both industry and the research community. The field was created out of necessity. Software systems were growing larger: systems of hundreds of thousands or even millions of lines of code were becoming commonplace. Clearly, Parnas, Brooks, Dijkstra and others in the 1960s through the 1980s-laid the foundations of the ideas underlying the field that is today called “software architecture” but what changed is that by the 1990s such large systems were becoming common."