Wallets & Security
One key is built to be shown. The other decides everything.
Your entire crypto ownership hangs on one key pair. One part you can show the whole world. The other must never be seen by anyone — not even "support". Confusing the two is how people lose everything.
The problem
Prove you authorised this payment. Without showing the key.
The network has never met you. It needs proof that the owner approved this move. There are two ways to try it — press one and see which one the panel will actually do.
One payment, two ways to prove it
NOTHING PROVED YETPRIV-KEY-STAND-IN-NOT-A-REAL-KEY
Public address — shareableADDR-STAND-IN-SAFE-TO-SHOW
Both strings above are obvious invented stand-ins, written for this page only. Nothing here is or resembles a real key or a real address.
Waiting. It will check whatever arrives against the public address above — that is the only thing about you it needs to know.
Pick one. Send them the key looks like the direct route. It is not.
A key is not a receipt. Handing it over would not prove this one payment — it would hand over the ability to authorise every payment, from any device, for as long as that key controls anything. There is no way to limit it to one transaction and no way to take it back afterwards. That is why the panel refuses, and why nobody legitimate ever asks. Anyone who does ask — including anything calling itself "support" — is telling you exactly what they are.
The wallet signs locally with the private key and transmits only the transaction plus its signature. The signature is your proof of authorisation: it shows the network the owner approved — without ever revealing the key. That asymmetry is the whole trick. Proof travels; the thing that produces the proof does not.
No — and this is the myth worth killing. An address only allows sending to you and viewing your public activity. Moving the coins requires control of the matching private key. Publicly visible addresses are part of the system's design, not a leak. The address is the mail slot: anyone can drop something in. The key is what opens the box. Share the first freely; never share the second.
The definition
Three claims that make the pair click.
Tap each card for what sits behind it.
Hands on
Four questions, answered twice.
Same four questions, two halves of one pair. Switch sides and read what changes.
Address (public)
Quick check — you want to receive payments and put something in a public profile. Only one of these three belongs there: your receiving address. Not your private key, not your seed phrase. Those two grant full control, and they never belong in profiles, chats or forms.
The bridge
Where each key does its work.
Four steps from money arriving to the network accepting it. Watch which step the key appears in.
"Not your keys, not your coins" is this lesson compressed into five words. It means: if you don't control the keys yourself, you don't fully control your coins technically — you're trusting a custodian instead. That can be a deliberate, reasonable choice. What matters is knowing which model you're using right now. Which is exactly what the next lesson is about.
Check yourself
Five questions.
Answers come straight from this lesson. Submitting completes it.