This article is contributed by Kamila Součkova
As the btrfs wiki says: “Btrfs is a new copy on write filesystem for Linux aimed at implementing advanced features while focusing on fault tolerance, repair and easy administration.” Although under heavy development, it has become stable enough for personal use, and there are plenty of reasons to try it. What distinguishes it from earlier filesystems is that it has been designed with scalability and robustness in mind: it can handle huge files (up to 16EiB — a lot!), it can pack lots of files and directories efficiently, has built-in error detection methods (checksums of data and metadata), support for transparent compression, integrated multiple devices support (RAID-0, RAID-1 and RAID-10 so far) and more — see here for a more complete list.
In this how-to I will focus on one particularly neat feature: snapshots. Btrfs allows you to make read-only or writable snapshots of the state of your filesystem without wasting space with redundant data. Together with YaST’s Snapper module, this makes tracking FS changes and undoing undesired modifications a breeze.