Field guide to self-held bitcoin

$ cat keys.txt

A private key is the secret that proves you are allowed to spend a particular bitcoin. Whoever holds it can sign a transaction, and no bank, support desk, or company can reverse a signature that was made correctly. A public address is different. It is the identifier others use to send you bitcoin, and sharing it does not give anyone the power to spend.

Most people never handle a raw private key. Wallet software generates keys for you and keeps them encrypted on your device. The practical rule follows from that: protect the material that can rebuild the keys, and you protect everything derived from them.

$ cat recovery-phrase.txt

Many wallets create a recovery phrase when you set them up: an ordered list of ordinary words, commonly 12 or 24 of them. The phrase encodes the master secret from which the wallet derives its keys. With the phrase and a compatible wallet, you can rebuild access even if the original device is gone.

That makes the phrase the most sensitive thing in your setup. Treat it as the key itself, because it is one.

• Write it by hand on paper or metal, and check each word against the original.
• Never type it into a website, a chat window, a form, or an app you did not install from its official source.
• Do not photograph it, keep it in a cloud note, or send it to anyone, including someone who says they are support.
• Keep the written copy somewhere that resists fire, water, and casual browsing.

A recovery phrase is not a password you can reset. If it is lost, or if someone else obtains it, there is no reset button.

$ cat custody-models.txt

Bitcoin is usually held in one of three broad ways. Each moves responsibility to a different place, so compare them against what you can actually maintain.

• Software self-custody. Keys live in a wallet app on a phone or computer. It is convenient for everyday use, and it depends on the security of the device it runs on.
• Hardware self-custody. Keys live on a dedicated device that signs transactions without giving the secret to the computer it connects to. It adds a physical step and one more object to keep safe.
• Custodial accounts. A company holds the keys and keeps the records for you. Day-to-day handling is simpler, but you rely on that company's security, operations, and terms, which are its rules rather than yours.

None of these is automatically right. The question is which one you can operate calmly, year after year, including on the day something goes wrong. btcaux does not rank or recommend particular products.

$ cat watch-only.txt

A watch-only wallet imports a public address or an extended public key. It can show balances and transaction history without holding any signing key, so it cannot spend. People use one to check on funds from a convenient device without exposing the keys that move them.

A watch-only setup is useful, but it does not back anything up. If you lose the watch-only app, you lose the view, not the coins. Control still depends on the recovery material.

$ cat backup-plan.txt

A backup plan is a short written note with four parts. Keep it on paper, date it, and update it whenever your setup changes.

1. What exists. The wallet type, roughly when it was created, and whether it uses an additional passphrase. Record that a passphrase exists, never the passphrase itself.
2. Where the recovery material lives. Name the locations, not the contents. Keep the note and the secret apart.
3. Who can act. Name the trusted person or process that can restore access if you cannot, and say what they are allowed to do.
4. How you check it. The date of the next drill and which drill it is. The recovery drills page lists them.

plan.txt
  what exists      one software wallet, set up on your own phone
  where it lives   recovery material on paper, in two separate places
  who can act      one trusted person knows the plan, not the secret
  next drill       on the calendar, with the checklist attached

Keep the plan private. If the wrong person reads it, they learn where to look. If nobody can find it, the plan does nothing, so share it only with people who will act on it.

For estate planning, tax treatment, or legal authority to act, speak with a qualified professional where you live. A written plan helps that conversation. It does not replace one.

$ cat threats.txt

• Phishing. Sites, messages, and calls that imitate a wallet, an exchange, or a support desk to collect your phrase. Legitimate software does not need your recovery phrase to help you.
• Single points of failure. One copy, one location, one person who knows, or an optional passphrase that exists only in your head.
• Physical damage. Paper that fades, water, heat, and handwriting that becomes hard to read over the years.
• Fake installs. Wallet software downloaded from a link in a message or an advertisement rather than from the project's own source.
• Rushed setups. Recovery material made in a hurry and never checked.

Each of these is preventable with a calm afternoon and a clear plan. That is why the recovery drills page exists.

This guide teaches concepts. It is not financial, legal, or tax advice, and it is not a recommendation to buy, sell, or hold any asset. Nothing here predicts prices.

Next, put the plan to work on the recovery drills page, and look up unfamiliar words in the glossary.