Explanation:
A digital signature is a cryptographic mechanism used to verify the authenticity and integrity of a digital message or document.

Digital signatures use asymmetric encryption algorithms, where the sender signs the message using their private key, and the receiver verifies it using the sender’s public key.

Digital signatures are widely used in secure email communication, financial transactions, and digital contracts to ensure non-repudiation and authenticity.

Additional Information:
Digital certificates issued by trusted Certificate Authorities (CAs) bind public keys to entities, ensuring secure key management for digital signatures.

Standards like PKCS and algorithms such as RSA and ECDSA are commonly used for generating digital signatures. Blockchain systems also rely on digital signatures for transaction validation.

Formal Definition:
A digital signature is a cryptographic method that ensures the authenticity, integrity, and non-repudiation of digital messages or documents by using asymmetric encryption.