Wormholes are regions of warped spacetime that enable instantaneous travel between distant locations. They were first generated and commercialized by CST co-owners Nigel Sheldon and Ozzie Fernandez Isaacs. Sheldon and Isaacs linked the first wormhole between Earth and Mars, meeting the 1st InterSolar Mars exploration team from Earth that had been sent into space long before.
The wormhole generators used by CST are capable of projecting wormholes across interstellar distances, although there are limits to their range.
The Commonwealth uses trains to travel from planet to planet. The wormholes are covered by pressure curtains that stop the atmospheres of the connecting planets mixing. Once the trains pass through the pressure curtain to the destination planet, the new atmosphere is fed into the compartments like a decompression chamber for divers to allow the passengers the time to get used to the new atmosphere.
The wormholes are also used for exploration, using them to survey new possible colonies - there is a CST exploration on Merredin.
The starship Second Chance used a continuous wormhole drive for FTL travel, something Ozzie Isaacs claimed was "hyperspace," something he worked to avoid in the first prototype wormhole, indicating there are several separate methods of wormhole travel.