What is AI, and how do I actually use it?

What tools like ChatGPT and Copilot really do, what they're good at, and where they trip up.

⏱ 6 min read · ▶ 1:16 video
The short version

AI chat tools are very good at working with words: drafting, summarizing, explaining and brainstorming. They are not always right, so treat them like a fast, eager assistant whose work you check, and don't paste in anything private.

So what is it, really?

"AI" (artificial intelligence) is a broad term for computer systems that do things we normally associate with human thinking, like understanding language or recognizing what's in a photo. When most people say "AI" today, they mean chat assistants such as ChatGPT, Microsoft Copilot, Google Gemini and Claude.

These are built on something called a large language model. It learned patterns from an enormous amount of text, and it writes answers by predicting, word by word, what a helpful reply would most likely look like.

Think of it like this: it's like a very well-read intern who has skimmed a huge library. They can write a decent first draft of almost anything in seconds, but they sometimes misremember things and say them with total confidence.

Good everyday uses

  • Write a first draft: an email, a job post, a thank-you note, a policy outline.
  • Rewrite or shorten: "Make this friendlier," "Cut this to three sentences," "Fix the grammar."
  • Summarize: paste in a long article (nothing confidential) and ask for the key points.
  • Explain: "Explain this insurance letter like I'm not a lawyer."
  • Brainstorm: names, gift ideas, meal plans, questions to ask a contractor.

How to ask so you get a good answer

The more context you give, the better the result. A simple recipe:

  1. Say who it's for. "Write an email to a long-time customer…"
  2. Say what you want. "…letting them know our prices go up in January…"
  3. Say how it should sound. "…warm, short, no corporate speak."
  4. Then refine. "Shorter." "Less formal." "Add a line thanking them." You can keep going back and forth.

Where it trips up

  • It can make things up. This is called a hallucination: facts, quotes, links or numbers that sound right but aren't. Double-check anything that matters.
  • It may be out of date. Some tools search the web, others only know what they learned during training.
  • It doesn't know your situation. For medical, legal, tax or financial decisions, use it to prepare questions, not to replace a professional.

Keep your private stuff private

Depending on the tool and your settings, what you type may be stored and, with some free consumer versions, used to improve the service. A good rule: don't paste passwords, financial account numbers, health details, or customer and employee information into a free AI tool. Businesses should use a work version with a clear data-protection agreement (for example, Microsoft 365 Copilot through a work account) and set simple rules for staff.

Try this today

  • Ask an AI tool to rewrite an email you've already written, then compare the two.
  • Ask it to explain something you've always nodded along to, like "What does my router actually do?"
  • Ask it a question you already know the answer to, and see how it does.

Test yourself: play AI or Not? or Prompt Builder, quick free games.