Okay kiddo, so you know how when we want to make a toy car move, we usually push it or use a battery to power it up? Well, it's kind of like that for spacecraft too!
But instead of using gas or liquid fuel to create a big explosion that pushes the spacecraft forward, some spacecraft use something called electric propulsion.
Electric propulsion uses electricity to create tiny, tiny electrical charges that push the spacecraft slowly but steadily forward.
It's kind of like the way one magnet pushes another magnet away when you hold them close together. The tiny electrical charges create a magnetic field that pushes the spacecraft forward in the opposite direction.
Even though it's slower than using a big explosion like a rocket, this kind of propulsion is very efficient and can keep a spacecraft moving for a long time without needing to stop for more fuel.
So basically, spacecraft electric propulsion uses electricity to create tiny, steady forces that move a spacecraft forward, kind of like how magnets push each other away.