Prim, short for or primitive, is a widely used slang term for humans or other sophonts who reject all but the most primitive technology.
Unlike Ludds, Prims do not actively seek to destroy higher tech civilisations, but merely to insulate or remove themselves from them. Examples include the inhabitants of New Gaia, Nuihaven, and those involved in various similar projects like True Planet Earth Tribe (tribal shamanic) and Back to the Neolithic (both in the Utopia Sphere). Not all prims live on the surface of a planet; in fact, most live in large orbital biospheres constructed by kindly AIs. Prim converts in civilized regions often take a vow to forsake technology and return to a simpler way of life, before traveling to isolated worlds or habitats (whether in the Outer Volumes or the Utopia Sphere) where they can isolate themselves from the civilized galaxy.
Many prim clades and phyles adopt austere spiritualist ideologies, whether theistic-religious or eco-conservative. Sometimes these are derived from religions or movements that originated on Old Earth, and often they are entirely novel and idiosyncratic to the local culture.