What is AI, in plain English

The short version

People use the words “AI” for a lot of different software. Right now, in ordinary life, it usually means a chat box that can write, rewrite, explain, or plan.

That software is useful when the job is a draft. It is a poor choice when you need a fact you cannot check, a judgment about a person, or a secret kept.

What a chat tool actually does

Most chat tools are built on a large language model. The model was trained on a huge amount of text. When you type, it predicts a likely reply, one small piece of text at a time.

That is why the reply can sound human. The tool is good at the shape of an answer. Sounding sure is not the same as being right. When a tool invents a fact, people call that a hallucination.

Some products add extra steps. They may search the web, read a file you upload, or run code. If yours does that, it should show you. If it does not show a source, do not assume it looked one up.

What it is good at

• Turning a rough note into a cleaner draft.
• Explaining a topic in simpler words, so you can go check the real source.
• Making a checklist, an outline, or a first pass at a plan.
• Practicing a conversation, as long as you supply the facts.

You can see examples on the use-case directory.

What it is bad at

• Knowing what happened in your life, your class, or your business unless you tell it.
• Keeping a secret. A chat is stored by the company that runs the tool, under that company’s rules.
• Fair judgments about a student, a customer, a patient, or a job candidate.
• Current facts, prices, laws, and medical decisions, unless you confirm them somewhere else.
• Doing the sending, paying, or signing for you. If a tool offers to take those steps, that is an AI agent. Keep a person in charge.

A simple way to try it

Pick one low-stakes job. A messy list. A too-long email. A paragraph you want in plainer words.

Say what you want, who it is for, and what “done” looks like. That instruction is a prompt. Read the result. Fix it. If the result is wrong, say what is wrong and ask again, or throw it away.

You do not need a special course to start. You do need the habit of checking.

Your information

The text used to train a model is called training data. Your chat is a later step. It is still not a diary. Some products use chats to improve the service unless you turn that off. The switch is in the product’s settings, and the wording changes.

Before you paste something, ask: would I be comfortable if this text were stored by a company I do not control? If the answer is no, leave it out. Type a blank like [amount] and fill it in after you copy the draft back to your own computer.