A digital signature is a method of using cryptography to confirm the genuineness and integrity of transactions, documents, or digital messages. It provides a way to prove that a particular piece of information was created by a specific entity and has not been tampered with.

A digital signature consists of cryptographic algorithms and key pairs. The entity generating the signature uses its private key to encrypt a hash (a unique representation) of the message or data. The resulting encrypted value, known as the digital signature, is appended to the message or transaction. To confirm the digital signature, the receiver or any other party can utilize the associated public key of the signer. By decrypting the signature with the public key, they can compare it to the calculated hash of the received message or data. In case the two values match, it confirms that the message has not been altered since the signature was created and that it was indeed signed by the expected sender.