This book will turn 50 soon. And some parts of it haven't aged that well. It uses Fortran (the one where arithmetic if was the norm, and logic if was the new thing) and PL/I. But that doesn't matter for the most part. What matters is the approach and the rules. The approach is to take a piece of code, analyse its failings, improve it, and derive a general rule. And for the most part the rules are still valid today. Let that sink in. The half life of technical books these day is a few years. This book's rules are mostly applicable after half a century. And that is remarkable in itself.

There are other notable things about it though. If you've read any other book by Kernighan ("Software Tools" and its Pascal version, "The Practice of Programming") you'll recognise his later style in incipient form. It's a rare view into how a programmer's views evolve and mature. And much the same for Plauger, though I've only read "Programming on Purpose" from his later work.

And for computing history or language geeks this is a glimpse into what computing looked like back then. What programmers had to work with (and mind you the book uses high level languages, not assembly). We've come a long way.

This was well worth reading.