A terminal is the thing that looks like it might be a computer, but nobody is home, it’s just connected to a modem. Or, maybe, if you’re lucky, The Computer of your university.
A terminal emulator is, well, an emulator, so you can use a 1970’s shell, right there on your computer, just like you can emulate and play Pong or Space Invaders…
Hope that helps
Axioms are not like the others, they’re assumed to be true even before considering any evidence or even arguments.