Although these terms are often mixed up and used interchangeably, this is not the case. terminal, console, TTY and shell are not the same. There are significant distinctions between each of these components. In this article, we clarify the meanings of these terms as they apply to UNIX/Linux operating systems…
All the differences
- Port: is an environment that accepts text input and displays output when some command is executed. In other words, it would be an environment that allows you to run a shell and execute command line commands. To give some examples, some well-known terminals are Terminator, Tmux, Xterm, etc.
- Console: is a physical terminal or device, a control computer with which you can interact with the system and have access to the terminal. However, it is currently used in another context. But it really is a computer consisting of a mouse, a keyboard and a screen.
- Shell: is a command line interpreter, an environment that allows programs to run and to be able to execute scripts to show the results in the terminal output. Some examples of shell can be ksh, bash, zsh, PowerShell, etc. If you want to see the shell you are using in your environment, you can run the command which $SHELL and the name will appear in the output.
- TTY (Teletypewriter): is the acronym for teletype, an obsolete electromechanical type equipment that was used in the past. In Linux and Unix operating systems it is used to refer to the standard terminal of the system and they appear numbered. To see information about it, you can use the command w.
- PTS (Pseudo Terminal Slave): it is a less known term, but also used. It refers to a session used when connecting to a Linux system via the SSH protocol or using some SSH client like Putty. In this case, you can also use the command w to view information.