emulation and simulation

I will add also my wording:

remember software(pc or embedded) depends on serial fetch-execute instructions. while hardware is direct(and parallel).

You can simulate hardware using software. i.e. the serial fetch-execute instructions can model the behaviour of direct hardware.

You can also produce another hardware platform to directly model your hardware and this is emulation without using software.

If you are modelling software itself with another software then this can be viewed as emulation as well.