Codes vs. Ciphers

Codes vs. Ciphers

The development of the electric telegraph in the early 19th century allowed for near-instant communication through wires across continents. This was much faster than sending a horseback rider carrying a bag of letters. However, the telegraph couldn’t directly send written letters drawn on paper. Instead it could send electric pulses. A short pulse is called a “dot” and a long pulse is called a “dash”.


In order to convert these dots and dashes to English letters of the alphabet, an encoding system (or code) is needed to translate from English to electric pulse code (called encoding) and at the other end translate electric pulses to English (called decoding). The code to do this over telegraphs (and later, radio) was called Morse Code, and was developed by Samuel Morse and Alfred Vail. By tapping out dots and dashes with a one-button telegraph, a telegraph operator could communicate an English message to someone on the other side of the world almost instantly!

A       ● ▬                                                    T       ▬
B       ▬ ● ● ●                                            U      ● ● ▬
C       ▬ ● ▬ ●                                           V     ● ● ● ▬
D       ▬ ● ●                                               W     ● ▬ ▬
E       ●                                                        X     ▬ ● ● ▬
F       ● ● ▬ ●                                            Y     ▬ ● ▬ ▬
G       ▬ ▬ ●                                              Z      ▬ ▬ ● ●
H       ● ● ● ●                                              
I        ● ●
J        ● ▬ ▬ ▬                                        1      ● ▬ ▬ ▬ ▬
K       ▬ ● ▬                                             2      ● ● ▬ ▬ ▬
L       ● ▬ ● ●                                           3      ● ● ● ▬ ▬
M       ▬ ▬                                               4      ● ● ● ● ▬
N        ▬ ●                                                5      ● ● ● ● ●
O        ▬ ▬ ▬                                         6     ▬ ● ● ● ●
P        ● ▬ ▬ ●                                        7      ▬ ▬ ● ● ●
Q       ▬ ▬ ● ▬                                       8      ▬ ▬ ▬ ● ●
R       ● ▬ ●                                              9     ▬ ▬ ▬ ▬ ●
S       ● ● ●                                                0     ▬ ▬ ▬ ▬ ▬
International Morse Code, with characters represented as dots and dashes.
Codes are made to be understandable and publicly available. Anyone should be able to look up what a code’s symbols mean to decode an encoded message.

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