What engines and fuels would interstellar species use for space travel?

[Airbrush]

Nuclear pulse propulsion. Eject tiny nuclear explosives to push a pusher plate or Medusa sail.

 

http://en.wikipedia.org/wiki/Nuclear_pulse_propulsion

 

Moving at such high speeds, how do you dodge anything in your path?

Edited September 30, 2014 by Airbrush

[Anthony Morris]

I always loved the bussard ram-jet idea but understand that there would be a pile up of ions in front of the ship. What if those ions were directed around the ship's sides and pushed behind it using electromagnet arrays all along the ship? Like some species of bacteria that use little flagella to push against the water they are in. no need to carry propellant. nuclear or fusion power plants to provide power.

[roblus]

This is ok.

 

water ---> h2(and oxygen) ---> pellets --> nuclear fusion (activation: nuclear fission)

 

and

 

solar energy ---> photovoltaic propulsion.