IT Specialist – Software Development Practice Test

Digital signatures rely on creating a small, fixed-size fingerprint of the data (a hash) and then signing that fingerprint with the sender’s private key. The hash acts as a compact representation of the content, so if any part of the data is altered, the hash changes and the signature won’t verify. This is why hashing to detect alterations is the core idea behind signatures: it provides integrity and helps confirm who signed the data. The other statements describe related concepts that aren’t the signing process itself—encrypting with a public key is about confidentiality, a website certificate is about binding an identity to a key, and compression is separate from security.