Wine is an Open Source implementation of the Windows API on top of X, OpenGL, and
Unix.
Think of Wine as a compatibility layer for running Windows programs.
Wine does not require Microsoft Windows, as it is a completely free alternative
implementation of the Windows API consisting of 100% non-Microsoft code,
however Wine can optionally use native Windows DLLs if they are available. Wine
provides both a development toolkit for porting Windows source code to Unix
as well as a program loader, allowing many unmodified Windows programs
to run on x86-based Unixes, including
Linux,
FreeBSD,
Mac OS X, and
Solaris.
More information can be read in the articles Why Wine
is so important, and Debunking Wine Myths.
If you are wondering how well a particular application works in Wine, please
examine the Applications Database. For
installation instructions and step-by-step help with running Wine, take a look
at the User Guide.