FUSE is particularly useful for writing virtual file systems. Unlike traditional filesystems, which essentially save data to and retrieve data from disk, virtual filesystems do not actually store data themselves. They act as a view or translation of an existing filesystem or storage device. In principle, any resource available to FUSE implementation can be exported as a file system. See Examples for some of the possible applications.
Released under the terms of the GNU General Public License and the GNU Lesser General Public License, FUSE is free software. The FUSE system was originally part of A Virtual Filesystem (AVFS), but has since split off into its own project on SourceForge.net.