A teleprinter (teletypewriter, teletype or TTY) is a now largely obsolete electro-mechanical typewriter which can be used to communicate typed messages from point to point through a simple electrical communications channel.
It had a very limited character set, and poor print quality. The printer was often linked to a punched tape punch and [...]

Almost in parallel with Germany’s telex system, Bell Labs in the 1930s decided to go telex one better, and began developing a similar service (with pulse dialing and all!) called “Teletype Wide-area eXchange” (TWX).
TWX originally ran 75 bits per second, sending Baudot code and dial selection. However, Bell developed a second generation [...]

Telegraphy is the long distance transmission of written messages without physical transport of letters. This definition includes recent forms of data transmission such as fax, email, and computer networks in general. (A telegraph is a machine for transmitting and receiving messages over long distances, i.e. for telegraphy.)

Before the internet came into [...]