Torchship
Torchships are spacecraft which use Fusion Rocket propulsion, commonly referred to as a Torch. This is the most common type of propulsion system for spacecraft in the Blue Planet setting.
Fusion rocket drives use plasma from a fusion reactor to generate thrust. The plasma is released from the reaction chamber into a secondary magnetic field bottle where it is heated sufficiently to completely ionize the plasma, and then ejected through a thrust chamber.
Torch drives have the advantage of being able to provide very high levels of thrust, but also burn through hydrogen fuel very quickly. This makes them most suitable for applications where high-G, short duration burns are required. Most ships built for in-system travel rely on Torch drives, as do GEO and Incorporate military vessels which need to be able to rapidly change direction and speed.
Because Torches are most efficient at maximum thrust, torch ships covering long distances will accelerate very rapidly and then coast in zero-G for most of the distance to their destination. Commercial torch ships usually have a maximum thrust of .5 to 1.5Gs. Military ships and high-speed courier vessels may have drives capable accelerations of up to 5Gs, although human crewed ships will rarely attempt to maintain it for very long.