Back in the early 1980’s when I worked for IBM, I was able to acquire my own IBM PC and experience my own form digital frontierism. Today I really wish I had a logbook at hand with a record of everything I did as my ability to recall those details has faded with age. A couple of those memories that still do remain with me involve two obscure languages: APL and FORTH. And then there was Borland Turbo Pascal.
In those early days of the 1980’s, memory wasn’t an infinite field; it was a precious, finite resource. While most of us were content living with the structured guardrails of BASIC, there was a subset of us drawn to the elegant, stripped-back world of FORTH.
Learning FORTH felt less like coding and more like learning a new way to breathe. It was lean. It was efficient. It stripped away the overhead of high-level syntax until it was just you, the dictionary, and the stack. There was an honesty to it—no hidden abstractions, just a direct conversation with the hardware.
Then, of course, there was the hurdle of Reverse Polish Notation (RPN). Grokking the stack meant rewiring your brain. You couldn’t just state an operation; you had to prepare the world for it first. You pushed your data onto the stack, one piece at a time, and only then did you call the action. It was a rhythmic, almost percussive way of thinking: Input, input, act.
“In FORTH, you don’t just write programs; you build a language to solve the problem.”
This “bottom-up” philosophy changed the relationship between the creator and the machine. You weren’t just a user; you were an architect of your own vocabulary. To define a new “word” in FORTH was to permanently expand the capabilities of your environment. It was a recursive journey where every small success became a building block for the next complexity.
Looking back, those days with the IBM PC and the stack weren’t just about efficiency. They were about the discipline of clarity. When resources are limited, your thinking must be precise. The difficulty of RPN wasn’t a bug—it was a feature that forced you to understand the flow of data at its most fundamental level.