They were used in telegrams between various parts of the railway system, such as offices, stations, locomotive depots and goods yards.
[1] Many businesses of all kinds identified their telegraphic address, as well as their telephone number, on their stationery.
They stood for phrases, thereby saving time and reducing the likelihood of errors in the message.
An example of how one code word replaced many normal words, the longest code message in the telegraphic lexicon was Ryzy, which, with the addition of a number and location, translates as follows: Vehicle No ..... may be worked forward to ..... behind the brakevan of a suitable goods train during daylight provided locomotive branch certifies fit to travel.
Guard to be given written instructions to carefully watch vehicle en route.In this example, one code word replaces 90 others.