Welcome to The Art of Precision! In the last series — Events: When Something Happens → Action — you learned how computers listen for things that happen and run commands in response: An event is something that happens — a tap, a click, a timer, a sensor reading Events have triggers (what causes them) and responses (what the program does) Programs can listen for many events at once When an event occurs, the program runs the matching decomposed sequence of commands That series answered: what starts the instructions running? Now the question is: what makes those instructions actually work correctly? You can give a computer a command. You can trigger it at the right moment. But if the command is even slightly unclear — if it says "a bit" instead of "exactly 30 seconds", or "somewhere near" instead of "at the corner of Park Road and Main Street" — things go wrong. This series is about precision : the art of writing instructions so clear and exact that there is only one possible way to carry them out. What You Learned Last Time Idea What It Means ------ -------------- Event Something that happens that a program can notice and respond to Trigger The thing that causes the event Response The commands that run when the event occurs Event listener A program waiting and watching for a specific event What You Will Learn in This Series Post The Big Idea ------ ------------- Vague vs Precise Why "make tea" is not an instruction, but a 7-step recipe is Computers Are Completely Literal Computers do exactly what you say — not what you meant Precision in Real Life GPS directions, medical dosages, music notation — precision is everywhere Putting It All Together A complete worked example where precision makes the difference between success and failure What If GPS Was Vague? Imagine your GPS said: "Turn somewhere near the big roundabout, then go a bit further, then you are roughly there." You would get lost. Not because you are bad at following directions — but because the directions are not specific enough to follow correctly. Now imagine it says: "In 200 metres, turn right onto Park Lane. Continue for 1.2 km. Your destination is on the left." That is a different experience entirely. Precision is not about being picky. It is about being clear enough that only one correct action is possible. Questions People Ask My child is 9. Is "precision" too abstract an idea for that age? The word is abstract, but the lessons are not. Children already meet precision every day — following a recipe, arguing about the rules of a board game, being told "tidy your room" and having no idea what that means. Every activity in this series is physical: drawing, hiding objects, reading the back of a shampoo bottle. The word can wait; the habit cannot. Do we need to have read the earlier series first? It helps, but it is not essential. Each post explains itself, and the links back are there if you want them. If this is your first stop, start from the beginning — the whole path takes a handful of weekends. Is this teaching my child to code? Not yet, and deliberately so. There is no code in this series. What it teaches is the habit of writing instructions that cannot be misread — which is the part most beginners never get taught. When real code does arrive, a large share of the errors are precision errors, not typing errors. How is precision different from just being fussy? Fussiness adds words. Precision removes doubt. Vague vs Precise covers this directly: an instruction can be too wordy as well as too vague, and burying the action in detail is its own kind of failure. Judging how much detail a particular reader needs is the real skill — and it improves writing and speaking, not just programming. How long does this series take? Four posts. Each is a 5–10 minute read plus one activity of about ten minutes. An afternoon covers the lot, or spread it across a weekend. Nothing to install, nothing to sign up for, no computer required. A Note for Parents and Teachers This series teaches precision — the difference between an instruction that can be read one way and one that can be read ten. It uses GPS directions, recipes, prescriptions and sheet music to show that this is not a computer problem at all: it is what every field does when the instructions really have to work. The companion idea, that computers are completely literal, reframes a frustrating experience as a fair one. The computer did what it was told. The instruction was the problem. The best way to use it is in pairs, out loud. The one to do first is The Shape Description Game in Vague vs Precise: two people, back to back, one describing a drawing and the other copying it blind. It takes ten minutes, it is very funny, and children work out the lesson themselves — the round with numbers in it comes out right, and the round without them does not. In a classroom, each post is one lesson: read it, run the activity as a pair exercise, then use the "Check Yourself" questions as the plenary. The Shape Desc…