Pseudo-terminals, or pseudo teletypes, are applications that run under a Terminal or teletype and emulate its behavior. It's a very convenient way of creating interactive software that is capable of running inside a Terminal without any graphical interface. This is because it uses the Terminal itself to emulate one.
Understanding pseudo-terminals
Beginning with teletypes
Teletype (TTY) or teleprinter is the name for typewriters with an electromechanical system that was controlled through a serial port. It was connected to a computer that was capable of sending information to the device to print it. The data was made by a sequence of finite symbols such as ASCII characters, with a fixed font. ...
