A Hyperdrive propels a ship within Hyperspace faster than the drift current will carry it. Propution within Hyperspace requires a mix of combustable fuel and reactive material that Dark Matter can act against. Liquid Thrust Anatine Fuel (LTAF) can provide that momentum, but at a cost. LTAF, due to the rare Anatine crystal dust, is a very expensive fuel to burn. The richest mining operations in the galaxy deal in its creation.