And for those who keep using the word 'emulator', I don't think you know what that word means. Wine itself is an acronym for Wine Is Not an Emulator - And indeed it's not an emulator, it's a compatibility layer. It provides Windows applications with translated system calls, rather than attempting to emulate a full Windows environment.
Emulator has different meanings depending on context. In the context of computers, it often means instruction set emulation (which wine obviously doesn't do). In some other contexts (for example, printer emulators) it is a lot more broad, and means implementing support for some proprietary control language (hp-gl or pcl for example, when your printer natively speaks postscript).
Wine is an implementation of microsoft defined apis. In some contexts, this can mean emulation, in other contexts it does not. The term emulation is itself a very general term.