Terminology
Some of the terminology commonly used in unix systems can be confusing.
Computer/System
Computer/System Terminal (TTY)
The terminal is an electronic or electromechanical device used for communicating data with a computer or computing system. This once included teletypewriters (TTY), punched card readers and printers.
We now have computers with a keyboard and video monitor. The linux terminal is a piece of software that sends your input and receives output. It does not process your input.
Computer/System Console
A computer console is the output text entry and display device for system messages via a terminal. This includes a keyboard and video monitor.
A linux console is a way for the kernel and other processes to output text-based messages to the user as well as receive text-based input. The console will multiplex multiple virtual terminals.
Unix Shell (Command Line Interpreter)
A unix shell is a piece of software that users employ to type commands, utilizing command languages and scripting languages. This includes sh, ksh, csh, tcsh, bash and zsh.