Google File System

The Google File System is a scalable distributed file system invented by Google and described in a paper. The paper is openly available, but the file system itself is proprietary, used internally in Google's networks. It's distinct from Google Drive, a distributed filesystem that's accessible by the public via Google's software (though the back end of Google Drive may well be implemented on a Google File System).

Links

 * Google paper describing Google File System
 * Wikipedia article