The Wine project aims to allow a PC running a Unix-like operating system and the X Window System to execute x86 programs for Microsoft Windows. Alternately, those wishing to port a Windows application to a Unix-like system can compile it against the Wine libraries.
The name 'Wine' derives from the recursive acronym "Wine Is Not an Emulator" (rather, it implements a compatibility layer), although some have used the unofficial expansion "Windows Emulator". While the name sometimes appears in the forms "WINE" and "wine", the project developers have agreed to standardize on the form "Wine". The recursive acronym Wine resembles that of LAME (Lame Ain't an MP3 Encoder).
Wine, as free software, uses the GNU Lesser General Public License (LGPL). The Wine project originally released Wine under the same MIT License as the X Window System, but owing to concern about proprietary versions of Wine not contributing their changes back to the core project, work as of March 2002 has used the LGPL for its licensing.
The Wine developers released the first beta version of Wine (version 0.9) on October 25, 2005 after 12 years of development.