DPM's Manufacturing Hub functionality supports both versions and alternatives.
In Process and Resource Definition, a version represents a specific stage in the development of a given process. Multiple versions may be saved for each process as it is being developed, and may be referred back to when necessary.
When a new version of a process is created, it replaces the previous version of the process (and its children) in the PPR tree. The previous version is saved away, and any further modifications to the process only affect the new version.
An alternative represents a particular implementation of a process. Different process definitions (or alternatives) can be defined to accomplish the same task, and these alternative processes may be developed in parallel-independently of one another.
As an example, suppose that a person begins work on defining a process: