[spicybright]

It's pretty interesting how it does this too.

Legally they can't copy source code from windows, so they have to do something called block box reverse engineering.

That just means they can't look at the code, but they can try to copy exactly how the code works. This is for legal/copyright reasons.

It's really impressive so far. Windows is a complicated beast that has been built up since the early 90's without much old functionality being thrown out.