Wine allows OS X to run Windows applications.
This listing is for the official Wine release, which only contains source code. Winebottler is a tool that allows you to purchase Wine specifically for OS X.
Wine, originally an acronym for "Wine Is Not an Emulator", is a compatibility layer that allows Windows applications to run on many POSIX-compliant operating system, such as Linux OS X and BSD. Wine does not simulate internal Windows logic like a virtual emulator or virtual machine. Instead, Wine converts Windows API calls into POSIX calls automatically, eliminating memory and performance penalties and allowing you integrate Windows applications seamlessly into your desktop.
Version 5.0: Latest Developer build v5.7