THE CLASSICAL APPROACH TO SOFTWARE DEVELOPMENT
To understand the importance of TDD, it's necessary to see the road that led to it. Over the past 50 years the practice of software development has constantly evolved in an effort to find a balance between the needs of the business, the capabilities of the current technology, and the methodology in which developers are most productive. Missteps have occurred along the way, but even they were important as a means of determining which techniques and methodologies were evolutionary dead ends. This chapter reviews the road to TDD.
A Brief History of Software Engineering
Software development for business began during the age of the mainframe. Each hardware vendor seemed to have its own unique platform and paradigm for developing software. Sometimes these systems were similar enough to each other that developers could move from job to job and platform to platform with very little friction. Other times it was like starting from scratch. Although the basic concepts of computing were the same, each vendor had its own, sometimes very unique take on those concepts. Languages were archaic, often requiring many lines of code to do the simplest things that we take for granted today. And many times what worked in one implementation of a language or platform didn't work quite the same way in another.
The mainframe was a large, expensive piece of equipment. Many companies didn't own one, so the concept of the service bureau was born: Companies with ...