The development of blockchain wallets starts with the creation of a set of keys known as the public and private keys. These keys are used to mathematically secure the crypto.

1.  When you share your wallet address with someone, they will always send you cryptocurrency to your public address. Instead of being your wallet address, the public address is a hashed version of it.
2. As your private key is linked to your public key and consequently to your wallet address, it is the only one that can be used to unlock the wallet's contents by decrypting the data that the sender of the coins has encrypted.
3. The wallet owner will use their private key to sign a transaction before submitting it to the blockchain network to send cryptocurrency. Once the transaction has been made public, the network's nodes, who operate as verifiers, will utilize the related, publicly available public key that was used to sign the transaction to check that it is genuine and legitimate before allowing it to proceed.