Morse code

Morse code was designed in 1836 by Samuel Morse and his assistant Alfred Vail for the electrical telegraph. It is both an alphabet (each letter has a representation) and a transmission protocol: a dash is three times the length of a dot, and the inter-letter gap is three times the inter-symbol gap.

Principle

Each letter maps to a sequence of dots (short signal, · or .) and dashes (long signal, — or -). Code length follows letter frequency: E = . (one unit) is shortest because it’s English’s most common letter; Q = --.- is longer.

Extract of the international table:

A = .-      J = .---    S = ...
B = -...    K = -.-     T = -
C = -.-.    L = .-..    U = ..-
D = -..     M = --      V = ...-
E = .       N = -.      W = .--
F = ..-.    O = ---     X = -..-
G = --.     P = .--.    Y = -.--
H = ....    Q = --.-    Z = --..
I = ..      R = .-.

Between symbols of a letter: a short gap. Between letters: a long gap. Between words: an even longer gap (often /).

Example

CIPHE → -.-. .. .--. .... .

Variants and extensions

• American Morse (railroad Morse) — historical variant with gaps inside symbols, harder to read.
• Wabun — Japanese adaptation of Morse to kana.
• Q code and Z code — standard abbreviations compressing common phrases (QTH = “position”, SOS = distress signal).
• Fractionated Morse — Morse where dots and dashes are themselves ciphered.

In culture

• SOS: ··· --- ··· — designed to be unambiguous regardless of segmentation.
• Still in use in aviation (VOR/DME beacons announce their ID in Morse), amateur radio (CW), and as a fallback in degraded conditions.

Cryptographic weaknesses

Morse is not a cipher — it’s a public encoding, as readable as ABC once you know the table. It can, however, camouflage a message on a punctuation-free line and serves as a transport layer before a real cipher.

In CipherChronicle

Morse opens up the sonic and rhythmic dimension of puzzles. Grids can alternate dots and dashes visually, or even be heard. It’s a natural bridge from classical ciphers to modern codes.