用比较正常的说法来说:如果你的软件能做被模仿系统能做的所有事情，那么它就是一个模拟器。如果它只是近似于系统(it或其他)的结果，那么它就是一个模拟器。

这两个术语之间的区别有点模糊。来自一个“模拟器”是允许您调试嵌入式系统的硬件的世界。记住那些允许你拥有ICE (In Circuit Emulation)功能来调试PC平台的产品，我发现术语“仿真”的使用对于模拟一块硬件行为的软件来说有点不恰当。

我对当前使用“仿真”一词的理由是，它可以“增强”功能，并且只与系统行为的“合理”近似有关。

ICE: (In Circuit Emulation) A piece of hardware that is plugged into a board in place of the actual processor. It allows you to run the system as if the actual processor was present. Typically these have a variant of the processor on them to actually execute the software with glue logic to allow the user to break executation and single step under hardware control. Some would also provide logging capability. Most modern processors development systems have replace ICE type emulation with JTAG Emulation, where the JTAG just talks to the processor via a special purpose serial link and all execution is perform by the processor mounted on the board.

软件模拟器: 0x86仿真器只关心是否能够执行0x86汇编语言，而不提供特定0x86处理器的精确的每周期行为模型。Bochs就是一个例子。QEMU做到了这一点，但也允许使用特殊的内核模块进行“虚拟化”。

模拟器: 德州仪器为软件开发提供了一个处理器的CYCLE ACCURATE行为模型，该模型旨在精确模拟特定处理器核心的行为，供开发人员在拥有工作硬件之前使用。

软件模拟器增强功能: BLEEM不仅允许你运行Playstation软件，还允许显示器输出比Playstation能够提供的分辨率更高的分辨率，并且还利用了可用的gpu的更高级功能。(即更好的混合和平滑纹理。)

模拟器:

Consider a situation that you know only English and you are in China. In order to interact with a Chinese person you need a translator. Now, role of translator is that it will seek input from you in English and convert to Chinese and and give that input to the Chinese person and gets response from the Chinese person and convert to English and give the output to you in English. Now that translator and Chinese person is the emulator. Both combine will provide similar functionality as if you were communicating with the English person. So hardware may be different but functionality will be same.

模拟器:

我想不出比SPICE或飞行模拟器更好的例子了。两者都将用与硬件行为相似的软件或数学模型取代硬件组件行为。

最后，哪种解决方案更适合项目需求取决于上下文。

用比较正常的说法来说:如果你的软件能做被模仿系统能做的所有事情，那么它就是一个模拟器。如果它只是近似于系统(it或其他)的结果，那么它就是一个模拟器。

我不认为模拟器和模拟器可以比较。两者都模仿某些东西，但不是同一推理范围的一部分，它们不在同一上下文中使用。

简而言之:模拟器被设计用来复制原始程序的某些特性，甚至可以在真实环境中替换它。模拟器的设计不是为了复制原物的特征，而是为了在人类看来与原物相似。没有了原有的功能，仿真器无法在实际环境中代替原有的功能。

An emulator is a device that mimics something close enough so that it can be substituted to the real thing. E.g you want a circuit to work like a ROM (read only memory) circuit, but also wants to adjust the content until it is what you want. You'll use a ROM emulator, a black box (likely to be CPU-based) with a physical and electrical interfaces compatible with the ROM you want to emulate. The emulator will be plugged into the device in place of the real ROM. The motherboard will not see any difference when working, but you will be able to change the emulated-ROM content easily. Said otherwise the emulator will act exactly as the actual thing in its motherboard context (maybe a little bit slower due to actual internal model) but there will be additional functions (like re-writing) visible only to the designer, out of the motherboard context. So emulator definition would be: something that mimic the original, has all of its functional features, can actually replace it to some extend in the real world, and may have additional features not visible in the normal context.

A simulator is used in another thinking context, e.g a plane simulator, a car simulator, etc. The simulation will take care only of some aspect of the actual thing, usually those related to how a human being will perceive and control it. The simulator will not perform the functions of the real stuff, and cannot be sustituted to it. The plane simulator will not fly or carry someone, it's not its purpose at all. The simulator is not intended to work, but to appear to the pilot somehow like the actual thing for purposes other than its normal ones, e.g. to allow ground training (including in unusual situations like all-engine failure). So simulator definition would be: something that can appear to human, to some extend, like the original, but cannot replace it for actual use. In addition the pilot will know that the simulator is a simulator.

我认为我们不会看到ROM模拟器，因为ROM不与人类交互，我们也不会看到任何平面模拟器，因为在现实世界中，飞机无法有一个替代物来执行相同的功能。

在我看来，模拟器或模拟器中的模型可以是任何东西，并且不必与原始模型相似。一个ROM模拟器模型将很可能是软件而不是硬件，MS飞行模拟器不能比它更软件。

这两个术语的比较将与当前选择的答案(来自Toybuilder)相矛盾，后者将差异放在内部模型上，而我的建议是，差异在于假的是否可以用于执行实际世界中的实际功能(确实在某些可接受的范围内)。

注意，飞机模拟器还必须模拟地球、太阳、风等，这些都不是飞机的一部分，所以飞机模拟器必须模拟飞机的某些方面，以及飞机的环境，因为它不是在这个实际环境中使用，而是在一个训练室中使用。

This is a big difference with the emulator which emulates only the orginal, and its purpose is to be used in the environment of the original with no need to emulate it. Back to the plane context... what could be a plane emulator? Maybe a train that will connect two airports -- actually two plane steps -- carrying passengers, with stewardesses onboard, with car interior looking like an actual plane cabin, and with captain saying "ladies and gentlemen our altitude is currenlty 10 kms and the temperature at our destination is 24°C". Its benefit is difficult to see, hum...

总之，模拟器是一个真实的东西，旨在工作，模拟器是一个假的，旨在欺骗用户。

在计算机科学中，模拟和仿真都从相同的输入产生与原始系统相同的输出;但是，仿真也使用相同的过程来实现它，并且由相同的材料制成。模拟使用与原始系统不同的进程。同样值得注意的是术语复制，它是两者的中间——使用相同的过程，但由不同的材料制成。

所以如果我想在我的PC上运行我的旧《超级马里奥兄弟》游戏，我会使用SNES模拟器，因为它使用相同或类似的计算机代码(进程)来运行游戏，并使用相同或类似的材料(硅芯片)。 然而，如果我想在我的个人电脑上驾驶波音747喷气式飞机，我会使用飞行模拟器，因为它使用的过程与原来的完全不同(没有实际的机翼、升力或空气动力学!)。

以下是摘自计算机科学术语表的准确定义:

模拟是一种系统模型，它捕捉了系统输入和输出之间的功能连接，但不一定基于与系统本身相同或相似的过程。

复制是一种系统模型，它捕获系统输入和输出之间的功能连接，并基于与系统本身相同或相似的过程。

仿真是某种系统的模型，它捕获系统输入和输出之间的功能连接，基于与该系统相同或类似的过程，并且由与该系统相同的材料构建。

参考文献:The Open University, M366 Glossary 1.1, 2007