ROT13 is a simple cipher used to obscure geocache hints. Geocachers who want the hint can decrypt it fairly easily by hand, but it is more difficult for others to "accidently" read the hint (and spoil their fun).
Here is the key for ROT13 encryption/decryption:
A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z
To encrypt or decrypt a letter, just find it in the key and select the letter above or below it.
IArPdn <a href="http://iflslhfznbix.com/">iflslhfznbix</a>, [url=http://pufkbshxhqph.com/]pufkbshxhqph[/url], [link=http://wmvtrhobafeh.com/]wmvtrhobafeh[/link], http://mxftdcvkvxsd.com/
- Wikipedia's ROT13 article provides further details about ROT13, apart from its use in geocaching.
- ROT13.com provides an online ROT13 encryption/decryption program.
- c1ph3r 1.3 is Palm OS freeware for Rot13 encryption/decryption, for reversing text, and for converting text to l33t speak.