** **** is a Unix utility which serves to find files on **filesystems. It searches through a prebuilt database of files generated by the command or by a daemon and compressed using incremental encoding. It operates significantly faster than, but requires regular updating of the database. This sacrifices overall efficiency (because of the regular interrogation of filesystems even when no user needs information) and absolute accuracy (since the database does not update in real time) for significant speed improvements, particularly on very large filesystems. was first created in 1982. The BSD and GNU Findutils versions derive from the original implementation. Their primary database is world-readable, so the index is built as an unprivileged user. command is also included in MacOS. (Merging Locate) and the earlier (Secure Locate) use a restricted-access database, only showing filenames accessible to the user. uses posting lists. Like and , it only shows files if would list it. Compared to, it is much faster, and its index is smaller.