Documents naturally become fragmented. This can happen for several reasons:
In all of the above cases, a branch will be created and their changes tracked separately.
In this example, Paul and Peter both edited a document at the same time resulting in the two branches.
Ideally, a merge should be performed as soon as changes can be agreed.
To merge these versions; select any of the heads of a branch; in the above example these are version 0.0.3 or 0.0.4.
Select the "Merge versions" panel which is illustrated below:
This will expand the merge console. In this example we have selected 0.0.4 and intend to merge with version 0.0.3. On more complicated documents, you could have multiple branches to choose from. You can only merge two branches at a time. If you want to overwrite the other branch you should use the reverting functionality.
Select "Merge" and your branches will be merged together:
Any changes will show up as "Tracked Changes" in Word for you to accept or reject as per normal: