Safety rules before you begin

Building an app means making accounts, paying for things, and letting software act on your computer. Five rules keep that safe. They are short. They are also the most important page in this guide.

1. Never type a password or a code into a chat

Never type a password, a bank account or credit card number, or a secret sign-in code into Claude, into any chat, or into an email. Claude never needs them. This guide never asks for them. Later parts show you how to give your app its own secret keys without ever pasting them into a conversation.

If a page, a message, or a person asks you to, stop and close it.

2. Nobody legitimate asks for your sign-in code

Codes that arrive by text, email or pop-up are for one thing: typing into a sign-in screen that you opened yourself. Apple, Google, your bank, Claude, and real support people never ask you to read one out or send it on. Anyone who does is trying to steal your account. Hang up, or delete the message.

3. Know what a scam looks like

A scam is a trick to get your money or your accounts. The common shapes:

• Urgency: "Your account will be closed in 24 hours."
• Prizes: "You have won" or "You have been selected."
• Fear: "Your computer is infected. Call this number."
• A link in an unexpected text or email that leads to a sign-in page.
• A caller who says they are from Apple, Google, Microsoft or your bank.

The defense is always the same. Do not click links you did not expect. Open your browser and type the official address yourself. Do not call numbers from pop-ups. If a call feels wrong, hang up and call the company back using the number on your card or on their official site.

4. Do not approve what you do not understand

Your computer and your phone ask permission for things: "Allow camera?", "Allow notifications?", "Allow this app to find devices on your network?". Later, Claude will ask "Allow?" before it runs something on your computer. Part 4 explains which of those to accept.

Until then the rule is: if you do not understand what you are allowing, choose Don't Allow, Cancel or No. Nothing breaks. You can always allow it later, when a step tells you to.

5. Keep a paper list and keep backups

Write your computer's sign-in password or PIN, your Apple Account or Google account password, and your email password on one sheet of paper. Keep it somewhere safe at home. Part 1 sets this up. Later parts show you how to back up your app's files after every change, so a mistake can always be undone.

About Claude itself

Claude is a program that predicts helpful words. It is often right and sometimes confidently wrong. It cannot see your screen unless you show it a screenshot. It does not know what happened in another conversation unless you tell it. Treat it as a skilled helper who needs clear instructions and a check on its work. The guide shows you how to give both.