One of the most common AccuRev operations is making changes to an existing version and then using the Keep command to save the changes in a new version. The version in your workspace created by the Keep command is called a real version, because it represents a change to the element. Other commands (Rename, Defunct, and Undefunct, for example) can create real versions in your workspace, too.
The Version Browser uses a solid black line to connect the existing version (called the direct ancestor or predecessor) with the new version.
Exception: versions created by merge, patch, and revert operations are connected using other colors. See Versions Created by Merge Patch and Revert.