• Win4Lin Home, which is targeted for the home or small business user.
• Win4Lin 9x (Formerly Win4Lin 5), which is targeted for the home user/hobbyist, or business users who do not require Windows 2000.
• Win4Lin Pro, which is targeted at power users who require Windows 2000 or XP.

Win4Lin runs on most 2.4.x or 2.6.x Linux distributions. Win4Lin 9x and Win4Lin Home require a modified kernel to work. For most users, the Win4Lin graphical installer will select, download, and install the appropriate binary replacement kernel, making patching the kernel unnecessary. However, there are some distributions that may require users to compile a vanilla kernel from source. Such distributions include Red Hat Enterprise Linux 3 and 4, and Fedora Core 3 and 4. Some Linux distributions include Win4Lin support in their default kernel or make a Win4Lin enabled kernel available, including: Gentoo, Linspire, SimplyMepis, and Xandros. Win4Lin Pro does not require kernel modification.

Wine

Wine, which stands for Wine Is Not a (CPU) Emulator, is an Open Source implementation of the Windows API (application programming interface) that runs on Linux and POSIX compatible operating systems. Wine is a compatibility layer that allows Windows programs to run on Linux. Wine is still under development, and it is not yet suitable for general use, however, many individuals use Wine to run Windows applications on Linux. WineHQ maintains an Application Database (http://www.winehq.com/site/about) of individual's success and failure reports running Windows applications with Wine. Other products mentioned in this article are based on Wine, including CodeWeavers CrossOver Office, and Cedega from TransGaming Technologies. Wine is Available for Free.