Primordials are beings that live in the Primordial Timeline (0). They are the original race.
Runners (n+1, n>0) are beings that are trying to escape the heat death of their universe but are unaware of the spiral collapse.
Primordial runners (0) are of the original race and discovered the truth of the reality they live and have been trying to escape forever.
Anomalies (n+1, n>0) people that have escaped their time but are unaware of the death of the universes.
Exceptions are beings that don't fit into the other categories. Exceptions are beings like the Time Gods and Freyja.