Gutenberg is a new editor developed with the aim to improve the user experience in creating and writing content. It has been developed since early this year and first introduced to the public at the Q&A session at the WordCamp Europe 2017.
At the moment, Gutenberg is being actively developed. You can download it from WordPress.org repo and test how it works. But it’s not recommended to use on the production sites.
Text Source from: https://metabox.io/gutenberg-and-meta-box/