╔═══════════════════════════════════════════════════════╗ ║ ║ ║ ████████╗██╗ ██╗███████╗ ║ ║ ╚══██╔══╝██║ ██║██╔════╝ ║ ║ ██║ ███████║█████╗ ║ ║ ██║ ██╔══██║██╔══╝ ║ ║ ██║ ██║ ██║███████╗ ║ ║ ╚═╝ ╚═╝ ╚═╝╚══════╝ ║ ║ ██████╗██╗██████╗ ██╗ ██╗███████╗██████╗ ║ ║ ██╔════╝██║██╔══██╗██║ ██║██╔════╝██╔══██╗ ║ ║ ██║ ██║██████╔╝███████║█████╗ ██████╔╝ ║ ║ ██║ ██║██╔═══╝ ██╔══██║██╔══╝ ██╔══██╗ ║ ║ ╚██████╗██║██║ ██║ ██║███████╗██║ ██║ ║ ║ ╚═════╝╚═╝╚═╝ ╚═╝ ╚═╝╚══════╝╚═╝ ╚═╝ ║ ║ ██████╗ ██████╗ ██████╗ ███╗ ███╗ ║ ║ ██╔══██╗██╔═══██╗██╔═══██╗████╗ ████║ ║ ║ ██████╔╝██║ ██║██║ ██║██╔████╔██║ ║ ║ ██╔══██╗██║ ██║██║ ██║██║╚██╔╝██║ ║ ║ ██║ ██║╚██████╔╝╚██████╔╝██║ ╚═╝ ██║ ║ ║ ╚═╝ ╚═╝ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝ ║ ║ ║ ║ ~ encode, decode, conceal, reveal ~ ║ ╚═══════════════════════════════════════════════════════╝
Rotate each letter 13 positions through the alphabet. A becomes N, B becomes O, and so on. The beauty of ROT13: encoding and decoding use the same operation. Apply it twice and you're back where you started.