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I see that they are different things but I really can't tell why. Some people say: "emulators are for games; virtual machines are for operating systems" I don't agree with this answers because there are emulators for platforms other than videogame consoles (AMIGA (?) )
Can you help me please?
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Virtual machines make use of CPU self-virtualization, to whatever extent it exists, to provide a virtualized interface to the real hardware. Emulators emulate hardware without relying on the CPU being able to run code directly and redirect some operations to a hypervisor controlling the virtual container.
A VM converts commands to and from a host machine to an entirely different platform, whereas an emulator creates an environment based on the host machine and does no converting.
The main difference between them is that emulation is the computer program's ability in an electronic device to emulate the behavior of another program or device. On the other hand, virtualization is the process of creating a virtual instance of computer hardware platforms.
While emulated environments require a software bridge to interact with the hardware, virtualization accesses hardware directly. However, despite being the overall faster option, virtualization is limited to running software that was already capable of running on the underlying hardware.
Virtual machines make use of CPU self-virtualization, to whatever extent it exists, to provide a virtualized interface to the real hardware. Emulators emulate hardware without relying on the CPU being able to run code directly and redirect some operations to a hypervisor controlling the virtual container.
A specific x86 example might help: Bochs is an emulator, emulating an entire processor in software even when it's running on a compatible physical processor; qemu is also an emulator, although with the use of a kernel-side kqemu package it gained some limited virtualization capability when the emulated machine matched the physical hardware — but it could not really take advantage of full x86 self-virtualization, so it was a limited hypervisor; kvm is a virtual machine hypervisor.
A hypervisor could be said to "emulate" protected access; it doesn't emulate the processor, though, and it would be more correct to say that it mediates protected access.
Protected access means things like setting up page tables or reading/writing I/O ports. For the former, a hypervisor validates (and usually modifies, to match the hypervisor's own memory) the page table operation and performs the protected instruction itself; I/O operations are mapped to emulated device hardware instead of emulated CPU.
And just to complicate things, Wine is also more a hypervisor/virtual machine (albeit at a higher ABI level) than an emulator (hence "Wine Is Not an Emulator").
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