Readers will likely surmise John's native intelligence while progressing through the book, but he often writes as though his experiences were commonplace. They were not. As one who has been down the same path, I can assure you that John is being disarmingly modest when he casually says I bought the book, read about the system, and began programming it. Computer manuals, especially in the early days, were written as reference books, not tutorials. The authors assumed that you knew what you were doing and just needed a refresher. The books would give a technical description of, say, a computer instruction, with no hint as to why or where you might use it in a program. That part was up to you. After the design and coding phase, every system had a different and sometimes maddening program translation process. This process was intended to take your program from the written source code to an executable program. Heaven help you if your program did run but failed in execution. Supplied debugging aids were few. As John describes, a program failure often reduced the programmer to reading core dumps in octal or hexadecimal to determine the cause. Reading core dumps, watching the pattern of the console lights, or simply listening to the noises the computer made (yes, they did) were finely tuned skills of experienced programmers.

In addition, hidden dangers would lurk for those brave enough to delve into or interface with operating system routines, which John did on a regular basis. I find it remarkable that he gained all the necessary expertise on his own, which would have required a significant number of hours of concentrated effort. Sometimes when things didn't work right, you just kept working on them till they did. It was said of our profession that any of us who had not seen the sun rise over a cpu—the computer's central processing unit—couldn't truly be considered a programmer. Given John's experiences, I suspect that he saw many sunrises in that manner. Along the way he simply invented ingenious solutions to the problems he encountered. And finally, in my experience it is highly unusual for someone to be equally adept at all three levels of development: application programming, systems programming, and hardware design and implementation. Most people are content to focus on one and call for help if in trouble with either of the others. Except, of course, for John.

As authentic dinosaurs, veterans of the early days of the computer revolution, John and I have traded many war stories. Through the years I gained some insights into John's personal and technical history, but this book filled in many gaps and added new experiences. At one level, John's story is a history of nearly sixty years of computing, beginning with vacuum tubes, core memory, and hand-soldered components. You can follow advances in the science of computers, both hardware and software, from the beginning of his career to the end. And then, on another level, you can come to understand John's work history, which is varied and wide-ranging. Both perspectives, in my view, are informing and fascinating.