This is extracted (with some rewording) from Computer terminal and virtual console, which has been closed with a hatnote linking to What is the exact difference between a 'terminal', a 'shell', a 'tty' and a 'console'?. Original poster was interested in relations and differences between a computer terminal and a virtual console/terminal. Which is dependent on the operating system? How is it related to text vs graphical terminals?
Quoted from Wikipedia:
A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system. Early terminals were inexpensive devices but very slow compared to punched cards or paper tape for input, but as the technology improved and video displays were introduced, terminals pushed these older forms of interaction from the industry. A related development was timesharing systems, which evolved in parallel and made up for any inefficiencies of the user's typing ability with the ability to support multiple users on the same machine, each at their own terminal.
Quoted from wikipedia:
A virtual console (VC) – also known as a virtual terminal (VT) – is a conceptual combination of the keyboard and display for a computer user interface. It is a feature of some operating systems such as UnixWare, Linux, and BSD, in which the system console of the computer can be used to switch between multiple virtual consoles to access unrelated user interfaces. Virtual consoles date back at least to Xenix in the 1980s.