The Filing Open Service Interface Definition (OSID) is an O.K.I. specification.
OSIDs are programmatic interfaces which comprise a Service Oriented Architecture for designing and building reusable and interoperable software.

The Filing OSID provides platform independent storage

Computer storage

Computer data storage, often called storage or memory, refers to computer components and recording media that retain digital data. Data storage is one of the core functions and fundamental components of computers....

 and management of files and directories. Files and directories may be associated with metadata

Metadata

The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...

 such as owner, mimetype, quota, and versions. Implementations may be built using any technology including file systems, databases, WebDAV

WebDAV

Web-based Distributed Authoring and Versioning is a set of methods based on the Hypertext Transfer Protocol that facilitates collaboration between users in editing and managing documents and files stored on World Wide Web servers...

, or where any data access can benefit from a file system oriented interface.