Btrfs is a modern copy-on-write file system for Linux created by Chris Mason in 2007 for use in Linux. It has been declared stable in the Linux kernel since 2013. It comes with advanced features for fault tolerance, repair and easy administration. Btrfs uses copy-on-write for all files, which means if a file is modified/written to the storage, the file is not replaced but a copy of the file is created. This mechanism helps to create snapshots with minimum size as the unmodified files need not be copied for creating the snapshot.