Why are there several branches at the official documentation (e.g. 8.0.x, 8.1.x)? Why are there several branches (e.g. 8.0.x, 8.1.x) at the official documentation?



Is it planned that sub versions of Drupal 8 will be developed independently? 

If yes, then what's the point?
If no, then why are these branches mentioned in the documentation?
Drupal 8 made the switch to semantic versioning, and a shorter release cycle between minor versions.

Per release policy, there can be differences between minor versions.  In general, new minor versions are backwards compatible (or provide a BC layer), but can also introduce new features.  In addition, as minor versions get released, some functionality remains but becomes deprecated.

This is why there is different documentation for different minor versions; the document actually is slightly different.

To keep on top of changes in Drupal 8, monitor the list of Change Records or the Twitter account that announces each new one.