<architecture> When one system performs in exactly the same way as another, though perhaps not at the same speed. A typical example would be emulation of one computer by (a program running on) another. You might use an emulation as a replacement for a system whereas you would use a simulation if you just wanted to analyse it and make predictions about it.
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Nearby terms: EMS « emTeX « EMU8000 « emulation » emulator » Emulator program » EMX