A huge part of rocket science is the system of tanks, piping, valves and burners which deliver the fuel from the tanks to the engine. I try to explain why different designs exist and the advantages that more complicated designs deliver. To be clear, I'm not a rocket scientist, I only play one on the internet. Rocket engine diagrams are largely from Wikipedia with some Modification for narrative purposes https://commons.m.wikimedia.org/wiki/File:Gas_generator_rocket_cycle. https://commons.m.wikimedia.org/wiki/File:Pressure_fed_rocket_cycle.svg https://commons.m.wikimedia.org/wiki/File:Expander_rocket_cycle.svg https://commons.m.wikimedia.org/wiki/File:Staged_combustion_rocket_cycle.png#mw-jump-to-license