(APple File System) The latest file system for Apple products, including the macOS, iOS, tvOS and watchOS operating systems. Optimized for solid state drives (flash memory), APFS supports most of the features in HFS+, the previous Mac file system. APFS provides more crash protection than HFS+ with a "copy-on-write" meta-data feature, and it supports one nanosecond timestamps, compared to one second in HFS+. It also supports sparse files. With native encryption support, APFS combines features from iOS and OS X. APFS-formatted volumes are not supported in OS X Version 11.11 and earlier but can be shared via SMB. See file system and sparse file.