What is ReFS? Well, it's a file system that made its debut back in 2012 and builds upon NTFS. The platform brings enhanced support for large volumes and improved reliability for on-disk structures. In addition, the platform ties into existing APIs and "ReFS supports existing Windows and NTFS features such as BitLocker encryption, Access Control Lists, USN Journal, change notifications". While this change will not bring many noticeable improvements to the end user, it's an enhancement to the underlying technology that will deliver improved stability and performance which the end user can appreciate.