🔑 Keys & Wallets: Your Digital Vault

You don't store bitcoin

You don't "store" bitcoin inside an app.

You store a secret that proves it's yours.

Here's how that actually works.

Public vs. private keys

A public key / address is like an account number — safe to share so people can send you money.

A private key is the actual proof of ownership. It must never be shared with anyone.

One is your mailbox. The other is the only key that opens it.

The seed phrase

Your private keys are usually backed up as a seed phrase — 12 or 24 plain English words.

Whoever has those words controls the funds.

Not a password reset. Not a "forgot my login" link. Just those words.

Not your keys, not your coins

If an exchange or app holds your keys for you, you're trusting them the same way you'd trust a bank — they can freeze, restrict, or lose access to your funds.

Holding your own keys removes that dependency entirely.

It also moves the responsibility to you. That's the trade.

Try it: Seed phrase drill

Back up a practice wallet, lose the phone, and recover it from your words — with fake sats.

A zero-risk fire drill for self-custody. Your practice wallet holds 1,000,000 fake sats: back it up, survive a "lost phone," and restore it from your 12 words. Skip the backup and see exactly what happens — without losing a single real sat. Open the The Seed Phrase Game tool →

Quick check: Which key is safe to share with others?

1. The private key
2. The public key / address ✓
3. Neither — both must stay secret

Your address is meant to be shared — that's how people pay you. The private key is the one that must never leave your control.

Quick check: What controls access to bitcoin secured by a seed phrase?

1. Whoever possesses those words ✓
2. The wallet company that generated it
3. The email address on the account

There's no account, no company, and no recovery desk. The words *are* the ownership — which is why how you store them matters so much.

Next up

Now that you know what proves ownership, let's see what happens when you actually send money.