GygWin is NOT an emulator.
It is a highly competent _UNIX_ command line _equivalent_.
It is a command line interpreter that translates the Windows API to a very usable copy
of a real UNIX command line interpreter.
The _UNIX_ commands are executables in Windows format, not real UNIX executable
formats, but they respond the same.
Even the terminal responds to a large subset of the ASCII escape codes.
All in all, it is a good starter point if you do not intend to use the real thing.
Cygwin