A Pre-Skim Ship refers to a vessel designed and built before the invention and widespread use of Skim-Drive technology. These ships can navigate space using conventional, sub-light-speed propulsion methods (like ion drives, nuclear pulse or fusion engines). They cannot perform Skim travel and thus rely on traditional, slower methods to reach other star systems or destination within close range, usually requiring generations or having the crew cruogenical frozen or in stasis for interstellar journeys.