╔═══════════════════════════════════════════════════════╗ ║ ║ ║ ████████╗██╗ ██╗███████╗ ║ ║ ╚══██╔══╝██║ ██║██╔════╝ ║ ║ ██║ ███████║█████╗ ║ ║ ██║ ██╔══██║██╔══╝ ║ ║ ██║ ██║ ██║███████╗ ║ ║ ╚═╝ ╚═╝ ╚═╝╚══════╝ ║ ║ ██████╗██╗██████╗ ██╗ ██╗███████╗██████╗ ║ ║ ██╔════╝██║██╔══██╗██║ ██║██╔════╝██╔══██╗ ║ ║ ██║ ██║██████╔╝███████║█████╗ ██████╔╝ ║ ║ ██║ ██║██╔═══╝ ██╔══██║██╔══╝ ██╔══██╗ ║ ║ ╚██████╗██║██║ ██║ ██║███████╗██║ ██║ ║ ║ ╚═════╝╚═╝╚═╝ ╚═╝ ╚═╝╚══════╝╚═╝ ╚═╝ ║ ║ ██████╗ ██████╗ ██████╗ ███╗ ███╗ ║ ║ ██╔══██╗██╔═══██╗██╔═══██╗████╗ ████║ ║ ║ ██████╔╝██║ ██║██║ ██║██╔████╔██║ ║ ║ ██╔══██╗██║ ██║██║ ██║██║╚██╔╝██║ ║ ║ ██║ ██║╚██████╔╝╚██████╔╝██║ ╚═╝ ██║ ║ ║ ╚═╝ ╚═╝ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝ ║ ║ ║ ║ ~ encode, decode, conceal, reveal ~ ║ ╚═══════════════════════════════════════════════════════╝
Developed by Samuel Morse in the 1830s for telegraph communication. Each letter becomes a pattern of short signals (dots) and long signals (dashes). SOS (··· ─── ···) became the universal distress call because of its distinctiveness.