Passwords hashing

The crypt function to hash (originally encrypt) password dates back to the 70s, and used some rotor-based encryption, à la Enigma. Wikipedia has a nice article about its complete history.

In February 1997, Niels Provos switched OpenBSD’s crypt from DES to a BLOWFISH based hashing system that he invented with David Mazieres, called bcrypt. It landed in OpenBSD 2.1.

In 2007, Linux switched from MD5 to SHA-512, thanks to Ulrich Drepper, and is still using it as default hashing scheme as of 2019.

bcrypt is now widely used to hash passwords, and is supported by every major unix-like (FreeBSD, NetBSD, Linux, Solaris, …), is implemented in various languages, …

It’s a pretty strong algorithm, even by today’s criteria, and had a broad influence on how the world is storing passwords.