WinFS, short for Windows Future Storage, is the codename for a data storage and management system based on relational databases. It is being developed by Microsoft for use as an advanced storage subsystem for the Microsoft Windows operating system.
Implemented on top of NTFS, WinFS is a centralized data store for the Windows platform. It allows different kinds of data to be identified by metadata and use them to set up relationships among data, thereby giving a semantic structure to the data. These relationships can then be used by a relational database to enable searching and dynamic aggregation of the data, allowing the data to be presented in a variety of ways. WinFS includes a relational database engine, derived from SQL Server 2005, to facilitate this.