Terminal emulator A terminal emulator , terminal application, or term, is a program that emulates a video terminal within some other display architecture. Though synonymous with a shell or text terminal , the term terminal covers all remote terminals, including graphical interfaces. A terminal emulator inside a graphical user interface is called a terminal window.
A terminal window allows the user access to a text terminal and all its applications such as command-line interfaces and text user interface applications; these may be running either on a different one via telnet , ssh, or dial-up. On Unix-like operating systems, it is common to have one or more terminal windows connected to the local machine. Terminals support a set of escape sequences for controlling color, cursor position, etc.
Terminal emulators may implement a local echo function, which may erroneously be named " half-duplex ", or still incorrectly " echoplex ". Terminal emulators may implement local editing known as "line-at-a-time mode". This is mistakenly referred to as "half-duplex". In this mode, the terminal emulator only sends complete lines of input to the host system; the user enters and edits a line, but it is held locally within the terminal emulator as it is being edited. At that point, the entire line is transmitted.
Line-at-a-time mode implies local echo, since otherwise the user will not be able to see the line as it is being edited and constructed. However, line-at-a-time mode does not require local echo; when entering a password, for example, line-at-a-time entry with local editing is possible, but local echo is turned off. The complexities of line-at-a-time mode are exemplified by the line-at-a-time mode option in the telnet protocol. To implement it the Network Virtual Terminal implementation provided by the terminal emulator program must be capable of recognizing and properly dealing with "interrupt" and "abort" events that arrive in the middle of locally editing a line.
In asynchronous terminals data can flow in any direction at any time. In synchronous terminals a protocol controls. IBM based terminals used with IBM mainframe computers are an example of synchronous terminals, they operate in an "screen-at-a-time" mode.
Users can make numerous changes to a page, before submitting the updated screen to the remote machine as a single action. Terminal emulators that simulate the protocol are available for most operating systems, for use both by those administering systems such as the z9, as well as those using the corresponding applications such as CICS.
Additionally, programs have been developed to emulate other terminal emulators such as xterm and assorted console terminals. Some emulators refer to a standard, such as ANSI ; such programs are available on many platforms ranging from DOS and Unix to Windows and macOS to embedded operating systems found in cellphones and industrial hardware.
It is one of the first notebook-style computers, featuring a keyboard and liquid crystal display, in a battery-powered package the size and shape of a notepad or large book, it was made by Kyocera , sold in Japan as the Kyotronic Although a slow seller for Kyocera, the rights to the machine were purchased by Tandy Corporation ; the computer was sold through Radio Shack stores in the United States and Canada and affiliated dealers in other countries. It became one of the company's most popular models, with over 6,, units sold worldwide; the Olivetti M and the NEC PC and PC were built on the same Kyocera platform, with some design and hardware differences.
It was marketed as a Micro Executive Work Station, although the term did not catch on and was dropped. The screen was made by Sharp Electronics.