Working on multiple documentation versions in parallel
Branching and updating previous versions allow you to work on multiple documentation versions in parallel.
When you need to work on a new documentation version that is based on an existing version, you can clone the documentation set used in that version. This allows you to use the existing content as a starting point for the next version.
When you clone an existing version, the DITA CMS creates a new container and automatically branches all the maps in that version. For each existing map, it creates a new version of the map with the same content as the source version.
The new version automatically reuses all the content objects from its source version. At this point, changes made in Version 1 are automatically propagated to Version 2.
Topics, images, and resources can be reused in multiple versions, but you cannot use the same map in multiple versions. When you add a map to another version, the DITA CMS creates a new version of this map, which references another container. The topics, images, and resources that the map contains can be reused in other versions, but each map version is used in a single version.
Writers make the changes for Version 2 in the new map version. They can edit existing topics by branching them, they can add new ones, and they can also remove unnecessary ones, without impacting the source version. For example, the following diagram shows that Task 1 was branched: The DITA CMS has created a new version of Task1 (Task1 v2) and updated Container_v2 so that KeyB now references Task1 v2. Changes made to Task1 v2 will not be applied to Task1 v1.
Updating to previous versions
When version 2 of Task1 is updated to version 1, the DITA CMS updates Container_v1 so that KeyB now references Version 2 of the topic.