The Windows File System (WinFS) is Microsoft's new storage system for its upcoming SQL Server release. Along with serving as a database for structured, semi-structured and unstructured data, WinFS serves as a programming model that lets developers exchange data across applications and organize data in more constructive ways. According to Microsoft, it is not intended to replace NTFS, or the New Technology File System, which is used in Windows NT, but will serve as a link between NTFS and Vista's application layer.
Initially, WinFS was Microsoft's storage system of choice for its upcoming Windows Vista operating system, and WinFS, the Windows Presentation Foundation and Windows Communication Foundation made up the so-called "three pillars" of Vista. In 2004, Microsoft announced that WinFS would not be included in Vista, and in June 2006 the company said WinFS would be bundled into the next release of SQL Server and would not be a stand-alone product.