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Yes. The better ones smelled of fresh machine oil and chattered pleasantly as they worked.

Teletype Machines

Teletype Machine

Teletype machines were used from 1910 until about 1980 to send and receive characters over telegraph lines. They were made of electrical and mechanical parts. They printed characters on a roll of paper. Various mechanical actions of the machine were requested from a distance by sending control characters over the line. A common control sequence was "carriage return" followed by "linefeed".

In the early days of small computers (1972-1982) Teletypes were often the sole means of input and output to the computer. These Teletype machines printed with fixed-size characters (like their electric typewriter cousins). The tag used in HTML for fixed-size (non-proportional) font is <tt> -- which stands for "TeleType". This paragraph is set inside <tt> ... </tt> tags.

(Sadly, the <tt> tag has been deprecated and is no longer used.)

Some models of Teletypes could be used off-line (not connected to anything). The user could slowly and carefully type a message (or program) and have it recorded as holes punched on a paper tape. The device on the left of the machine in the photo is the paper tape reader/puncher. Once the paper tape was correct, the Teletype was put on-line and the paper tape was quickly read in. In those days, paper tape was mass storage.

The Web pages of the North American Communications Museum Off-site link have more information on Teletypes.


Can the bit patterns that are used to represent characters represent other things in other contexts?