There are four factions dominating the post-Crossout world. The player begins as an Engineer and after reaching reputation level 10, they can join one of the other three factions. Switching between the three presitge faction can be done fairly regularly later on.
Membership in a faction grants access to different vehicle parts crafting options and different rewards depending on faction level. Each factions is also suited for a different playstyle, from Lunatic glass cannons to Scavengers' literal tanks.