WoW64 (Windows 32-bit on Windows 64-bit) is a Windows operating system subsystem capable of running 32-bit native applications and is included in all 64-bit versions of Windows Bit (including Windows XP Professional x64 Edition, Windows Server 2003 x64 Edition, and Windows XP 64-bit Edition). WOW64 delivers all the differences between 32 and 64 bit Windows, in particular the structural changes of the same operating system.

File System
The Wow64 subsystem also deals with other major aspects of 32-bit applications. For example, it is involved in managing 32-bit application interactions with the Windows registry, which is quite different in the 64-bit operating system version, and provides a subsystem memory interface. The operating system uses the% SystemRoot% \ system32 directory for its libraries and executable files rather awkwardly. When 32-bit applications are running, WOW64 redirects requests for DLLs from this directory to% SystemRoot% \ sysWOW64, which contains old executables and old libraries.