Teleprinters used the 5-bit Baudot code (also known as IA2) to represent their character set.
The Baudot code was used asychronously with start and stop bits: the asynchronous code design was intimately linked with the electro-mechanical design of the first teleprinters.
Some teleprinters used [punched tape]? to record and replay messages. This was useful for situations in which access to the communication channel was at a premium.
Teleprinters were also used as the first interactive [computer terminals]?.
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