In Galactic Civilizations, the first known method of interstellar travel was the use of ancient structures called Star Gates. The Star Gates were capable of folding space and allowing ships to travel between any two of them. Many races used these, but they were unaware of other space-faring civilizations that they could not access with their own Star Gates.
This era ended when the youngest of the space-faring races, Humanity, who joined the interstellar club in the 22nd century, discovered a technology that would shatter the balance the Star Gates created: HyperDrive. With this new propulsion system, ships could travel great stellar distances on their own, redering the Star Gates obsolete. The advent of HyperDrive, and the power that it granted, destroyed the old balance. The other races found themselves in a race to explore, expand, colonize and ultimately conquer the galaxy.
HyperDrive is the most basic interstellar propulsion drive in the game. HyperDrive allows ships to travel great distances by folding space. While ships travel faster in folded space than normal, however, how fast they go depends on their base propulsion and how well it folds space. Further developments, such as the Impulse Drive and the Warp Drive, assess these conditions.