Commercial code (communications)

[1] Telegraph (and telex) charged per word sent, so companies which sent large volumes of telegrams developed codes to save money on tolls.

[2] Numerous special-purpose codes were also developed and sold for fields as varied as aviation, car dealerships, insurance, and cinema, containing words and phrases commonly used in those professions.

[6] Regulations of the International Telegraph Union evolved over time; in 1879, it mandated coded telegrams only contain words from German, English, Spanish, French, Italian, Dutch, Portuguese, or Latin, but commercial codes already frequently used nonsense words.

Telegrapher errors could sometimes cause serious monetary damages, which in one instance resulted in the United States Supreme Court case Primrose v. Western Union Telephone Company, in which a wool dealer argued that an error by a Western Union telegrapher cost $20,000 due to misread instructions.

The Supreme Court subsequently ruled Western Union was liable only for the cost of the message, $1.15.

The regulations of the International Telegraph Convention distinguished between "code telegrams", which it describes as "those composed of words the context of which has no intelligible meaning", and "cipher telegrams", which it describes as "those containing series of groups of figures or letters having a secret meaning or words not to be found in a standard dictionary of the language".