[Usenet: from `rotate alphabet 13 places']
The simple Caesar-cypher encryption that
replaces each English letter with the one 13 places forward or back
along the alphabet, so that "The butler did it!" becomes "Gur
ohgyre qvq vg!" Most Usenet news reading and posting programs
include a rot13 feature. It is used to enclose the text in a
sealed wrapper that the reader must choose to open -- e.g., for
posting things that might offend some readers, or
spoilers.
A major advantage of rot13 over rot(N) for other N is
that it is self-inverse, so the same code can be used for encoding
and decoding. See also
spoiler space,
which has partly displaced rot13 since non-Unix-based newsreaders became
common.
Give it a try:
This implementation is done in JavaScript by Henry Penninkilampi (rot13 email: urael@craavaxvynzcv.arg)
Other selected links about rot13:
Other stuff you may find here: