Private numeric code or private key, is numeric code – but you may never see your real private key. To make things more user-friendly, many wallet providers often encode your private keys in a way that you can record and remember more easily.
Many wallets use “seed phrase”, also known as “secret recovery phrase”, to unlock your wallet. If you open a crypto wallet with MetaMask, you will be given a random string of words that you use to unlock your funds. Your private key numeric code is hidden in the software behind this easy-to-use password.
Private key on the other hand is only for the wallet owner or commonly known as a wallet. The private key serves as the password for your crypto wallet and must be kept secret. What you have to understand is that if someone finds your private key, they will have access to all the crypto in that wallet and can do whatever they want with it.
However, if you store your crypto in an exchange wallet (like Coinbase or Binance) or with a custodian, then that company keeps your private key for you. In fact, it will control your funds in your own name.
The function of the private key, technically, is to “sign” transactions using your funds. Transactions using your funds cannot be validated by the network without your private key installed. The public key encrypts transactions, which can only be decrypted by the corresponding private key. This technology is called public key cryptography, sometimes abbreviated as CCP, or asymmetric cryptography.