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The difference between emulation and simulation?


Explain by Using as an example.
You want to duplicate the behavior of an old HP calculator, there are two options:
  1. You write new program that draws the calculator's display and keys, and when the user clicks on the keys, your programs does what the old calculator did. This is a Simulator
  2. You get a dump of the calculator's firmware, then write a program that loads the firmware and interprets it the same way the microprocessor in the calculator did. This is an Emulator
The Simulator tries to duplicate the behavior of the device.
The Emulator tries to duplicate the inner workings of the device.
More examples,
For Emulation,
You may know something about the case between Google and Oracle. In Brief, google implemented the same APIs(For Android) the java library provided to Java Developers to development Java applications. We can call it JRE Emulation Library. Also, in Google's GWT, it did similiar thing(weird that Oracle did not sue Google For this :) ) .
The Packages google emulated Java's Library.
java.io
java.lang
java.util

For Simulator,
when you develop Android , IOS or Windows phone applications, you don't need to plug in real device, just use the Simulator.



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