Why does Blackbird include ROT13?
ROT 13, a simple form of encryption that merely rotates the character values 13 values in one direction, was included for testing purposes. It is a classic exercise mentioned almost everywhere encryption is discussed. Rot 13 is more of an obfuscator than a form of encryption, and should not be relied upon. It can hide data from a packet sniffer or some other type of parser that is not “expecting” it.