I can attempt to explain as best I can...A lot of context will be lost, because a lot of the tools that were used at the time don't really have analogues, today. I will try to explain as best I can, which will be difficult because there were a lot of ways to do it: For a long time, until glass teletypes became inexpensive enough to use for every programmer, you would write your program (source code) down on paper, with pencil. Each instruction. Let's start circa 1977: Then you