Uryyb

Uryyb is the ROT13 encoding of the common English greeting "Hello." In online discussions, it appears as a playful, obfuscated form of a greeting rather than a separate term or language.

ROT13 is a simple symmetric substitution cipher that shifts each letter by 13 places in the alphabet. Because the alphabet has 26 letters, applying ROT13 twice returns the original text. The transformation is typically case-preserving, so "Hello" becomes "Uryyb" and "Uryyb" decodes back to "Hello."

Origin and usage: ROT13 originated in early online communities such as Usenet and bulletin boards as a lightweight way to hide spoilers, jokes, or sensitive content from casual readers. It remains popular in puzzle communities, code-golf forums, and other spaces where encoded messages are exchanged for entertainment or to bypass simple text filters.

Limitations: ROT13 provides no real cryptographic security; it is trivially reversible by applying the same transformation. Uryyb, as a specific instance, is simply a string produced by this cipher rather than a term with independent meaning.

See also: ROT13; Obfuscated text; Puzzle culture.