|Home » ACP » MD
MDYou'll get the message.
A message digest is a small stream of bytes that can cryptographically (and uniquely) identify a file.
Prior to macOS 10.12 Sierra, MD produced message digests with the algorithms MD5, MDC2, RIPEMD-160, SHA, SHA-1, and SHA-256. (The legacy MD for 10.6 and earlier offered MD2, MD5, MDC2, RIPEMD-160, SHA, and SHA-1.)
Starting with macOS 10.12 Sierra and moving forward, MD produces message digests for MD2, MD4, MD5, SHA, SHA224, SHA256, SHA384, and SHA512.
Researchers have broken some of the lesser algorithms and are growing suspicious even 160-bit algorithms may not be collision-free. The NSA are looking for another killer algorithm, but with MD you should be all right.
MD for macOS 10.12 Sierra constructs all eight message digests at once, with the results directly exportable in plain text to disk, so you won't be running a message digest on a file to test its integrity, you'll be comparing MD files instead.
With all eight algorithms working on your behalf, collision risks are more remote than ever.