Wallets, Public Keys and Private Keys
Your address is like an account number for receiving money; your private key is like your one and only signature stamp. Lose the private key and the coins are gone for good.
Risk warning: forex, CFDs, options, futures and crypto assets usually involve leverage or high volatility, and you can lose more than you put in. This lesson only teaches the concepts; all numbers are for illustration and are not investment advice.
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Text version · Crypto Basics, lesson 2: “Wallets, Public Keys and Private Keys”
Your address is like an account number for receiving money; your private key is like your one and only signature stamp. Lose the private key and the coins are gone for good.
A private key gives an address, not the other way round
private key → public key → wallet address: it only works in one direction. The seed phrase is a backup of the private key, and just like the key, it must never be given to anyone.
An address is like an account number for receiving
An address can be shared: others can only send money to it. Whoever has the private key controls the assets. Lose the key with no backup and no one can get it back for you.
Seed phrase: handwritten, offline, for your eyes only
12 or 24 words can restore the whole wallet. Write them down on paper and keep them offline: no photos, no cloud storage. Anyone claiming to be "support" who asks for your seed phrase is a scammer.
Key takeaways
- Private key → public key → address. Each step goes one way only and can't be reversed.
- Knowing your address only lets people send you funds; whoever has the private key can move your assets.
- A seed phrase is the backup of your private key: write it down by hand, keep it offline, and never share, screenshot or upload it.
- Anyone (including someone claiming to be support) who asks for your seed phrase or private key is running a scam.
Try it yourself
You can do these exercises in this lesson's interactive simulation:
- Click "Give your address to a friend": what can your friend do? Can they take your coins?
- Click "Send your private key to a stranger": what does the balance become? Who can use these assets now?
- Compare "Lost phone, but have the seed phrase" with "Lost private key, no backup": why can one be recovered while the other is locked forever?
- Click "Create new wallet", then "Show seed phrase", and read the warning that pops up.
Quiz and explanations
- 1. Which of these is safe to share publicly?
- Answer: Wallet address.An address is for receiving funds, so sharing it is safe.
- 2. What happens if you lose your private key and have no backup?
- Answer: Your assets can never be moved again.No organization can recover a private key for you.
- 3. Someone claiming to be "wallet support" says your assets are frozen and asks for your seed phrase to "unfreeze" them. What should you do?
- Answer: Refuse: anyone asking for a seed phrase is a scammer.Your seed phrase = full control of your wallet. A legitimate service will never ask for it.
Terms in this lesson
- private key (Private Key): The one credential that can move the assets in a wallet; whoever holds the private key controls the assets.
- public key (Public Key): A shareable key derived from the private key, used to verify signatures and generate addresses.
- seed phrase (Seed Phrase): A backup of your private key as a list of words; leaking it means handing over all your assets.
- wallet address (Address): A receiving account generated from the public key, safe to share with others.