Back to: Crypto Fundamentals from Zero
A wallet does one real job: it holds the private keys that prove you own your coins, and it signs the transactions that move them. It doesn’t “store” Bitcoin — the coins live on the blockchain; the wallet stores the key that unlocks them.
Key concepts
– Public address — like an account number. Safe to share; people send you coins to it. – Private key — the secret that signs. Never share it. Anyone who has it can drain the wallet. – Seed phrase — 12–24 words that recreate *all* your keys. It’s your master backup. Write it on paper, keep it offline, never type it on a website.
Types of wallet
| Type | Convenience | Security | Best for |
|---|---|---|---|
| Hot wallet (app/browser) | High | Lower | Small daily amounts |
| Cold wallet (hardware) | Lower | High | Long-term savings |
| Exchange account | High | Custodial — they hold your keys | Buying/selling only |
The golden rule
**Not your keys, not your coins.** If an exchange or app holds your keys,
> you’re trusting them — and exchanges get hacked. Real
> self-custody means the keys are yours alone.
Security checklist
1. Back up the seed phrase before adding real funds. 2. Store it offline (paper/metal). Screenshots and cloud notes get stolen. 3. Never enter your seed phrase into any website — legitimate software never asks for it. 4. Test with a tiny amount first.
Next lesson: buying your first crypto safely.