Historical information

In telecommunication, a commercial code is a code once used to save on cablegram costs.[1] Telegraph (and telex) charged per word sent, so companies which sent large volumes of telegrams developed codes to save money on tolls. Elaborate commercial codes which encoded complete phrases into single words were developed and published as codebooks of thousands of phrases and sentences with corresponding codewords. Commercial codes were not generally intended to keep telegrams private, as codes were widely published; they were usually cost-saving measures only.

This file includes correspondence between CAC, United Aircraft Corporation and North American Aviation reticence to manufacture the Pratt and Whitney Wasp engine.