Teletype devices pair a printout device with a keyboard input device. These were the first input-output devices for computers.
The original terminals (also called dumb terminals) were a combination of a cathode ray tube monitor with a keyboard. The most common manufacturers of terminals were the mainframe builders such as DEC and IBM. The monitor provides text-based output and the keyboard provides an interface for user input. These systems have only enough system memory and software to provide a basic text-only interface to another computer. All major processing is done at the main computer system to which the terminal is attached. There were many models of dumb terminals made by various manufacturers for this purpose.
Dumb terminals were the only way to interface to many of the older computers systems. Later, it became possible for a computer to run software that would emulate terminal behavior and allow any computer running a terminal emulation application to connect to any computer that only accepts terminal connections.
Here is a list of the most common and widely used terminals:
- IBM TN3270
- IBM TN5350
- Minitel
- VT-100
- VT-52
- Viewdata
Because these terminal types were so common, the first terminal emulation software mimicked these devices. Later, as emulation software became more common and sophisticated, new standards were developed. Today, there are additional terminal emulation types to choose from such as TTY (monochrome) and ANSI (multicolor display and other functions).