Rank simple checksum, hash, MAC, and digital signature by what security properties each one provides.

Each step up the ladder adds one guarantee: checksum→errors, hash→integrity, MAC→authenticity, signature→non-repudiation.

The dividing line — "malicious actor": the checksum and bare hash only survive accidental errors; a MAC and a digital signature survive a deliberate attacker, because they fold in a key the attacker doesn't possess (shared key for MAC, private key for signature).

Why the ladder is cumulative: each mechanism contains the one above it — a MAC is a hash with a key; a signature is a hash encrypted with a private key. So each new property is added without losing the previous ones.

Tip: Memorize the four columns left-to-right: Error → Integrity → Authenticity → Non-repudiation. Only the digital signature ticks all four.