Formulas, errors and code: if you work with spreadsheets
An optional lesson for people with spreadsheets, bills and baffling error messages. A formula from a plain-language description, an error explained, a small script, and checking someone else's code before you paste it — all of it available to someone with no technical background.
First things first: hit "Skip" with a clear conscience — nothing later in the course leans on this lesson. But if the words "Excel formula" or "error message" usually make your heart sink, stay for ten minutes: it turns out none of that has to be your job anymore.
If it is you, stay. People skip this topic saying «I'm not a programmer», and they're wrong: you don't need to be one, and the payoff beats several of the jobs from the previous lesson.
This isn't about writing an application. It's about four everyday situations where you used to have to call a friend who works in IT.
A spreadsheet formula. Instead of searching the web for "how to sum with a condition", describe the job in words and ask for the formula:
I have a table: column B has order totals, column C has dates. I need a formula that sums only the orders from July. Write it for Google Sheets and explain what each part does.
Notice the second half of that request — asking it to explain the parts. Without it you get a formula you paste and forget; with it, next time you write a similar one yourself.
An error on screen. A red box with English text is the most common reason people abandon what they started. Copy the whole error and ask: "What does this mean and what should I do? Explain it to someone with no technical background." Works for errors from programs, websites and phones.
A small script. Renaming two hundred files to a pattern, pulling every email address out of a document, sorting photos into folders by date. Describe what you need and ask not just for the code but for instructions on where to put it and how to run it. Say which system you're on — Windows or Mac: the commands differ, and without that the advice misses.
Someone else's code. A colleague sends you a snippet, a macro or a config and says "just paste this in". Before you do, ask the AI what the code does and whether there's anything dangerous in it. Thirty seconds, and the only sensible habit to have around other people's files.
Here's the catch. Code from an AI looks equally confident whether it's right or wrong. So how do you know when to trust it?
By the cost of being wrong. A formula in a copy of the spreadsheet, a script on three test files, an explanation of someone else's code — the cost is zero and you can check it by eye in a minute. But a command that deletes something or changes system settings is a different conversation: you don't run those without understanding every line. The rule is simple: on a copy first, on the real thing after.
If this leaves you wanting to build something of your own — a site, a bot, a small app — there's a separate course on vibe coding for that. But it all starts here, with a formula in a spreadsheet.
Short questions on the lesson — with an explanation for every answer.
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