A private key is a secret set of numbers that allows cryptocurrency to be sent from a specific wallet. Without a private key, you can’t withdraw cryptocurrency.
CEX.IO automatically generates and stores private keys for your crypto wallets. When you send crypto from a CEX.IO wallet, the transaction is signed by your private key. This key proves to the entire network that you have the authority to manage the funds at this wallet address.
A private key is naturally connected with the corresponding public key (or address). Unlike a public key (or your wallet address), however, a private key should not be disclosed, as it gives access to your funds.