Propellers housed in pods that can rotate 360 degrees, allowing the ship to steer without a traditional rudder.
A newer, quieter design where the electric motor is built into a ring around the propeller blades, reducing vibration and increasing efficiency. T_hrustrar
The simplest form, using pressurized inert gas (like nitrogen) released through a nozzle. They are safe but low-power. Propellers housed in pods that can rotate 360