An emulator is a hardware device that allows you to run your code in essentially a "perfect" representation of the target device. Short of actually running your code on the target device it is the most accurate way to see how your code will perform. The accompanying software normally allows you to see registers and step through your code from within a PC program although the actual execution occurs in the emulator hardware. The emulator hardware is normally attached to your PC via a serial connection.

A simulator is a software program that allows you to do about the same thing, but the simulator is entirely self-contained in the PC. There is no external hardware. You can simulate your program within the PC. A simulator is normally adequate for testing logic and algorithms that don't require external interaction and for tests that aren't highly speed-sensitive.

If you have the money for an emulator, go with an emulator. Depending on what you are testing, you may NEED an emulator. If you are testing algorithms and logic you may be able to get by with just a simulator.

Craig Steiner