RC4 with a Deck of Cards

There's a "simplified" implementation of it here: https://sos-cer.github.io/sssolitaire/

A stream cipher.

Old encryption algorithm, don't use it.

Infamous for "kerberoasting", among other exploits.

A formerly-popular cipher that works better than you'd expect given its extreme simplicity--simple enough that you can encrypt and decrypt it by hand with a deck of cards.

Nowadays it's insecure though, so you should never use it.