Your blood, water, and food is fuel, oxygen transports fuel, your heart is the engine, your eyes are cameras, illness is a system error and white blood cells are antiviruses, farts burps, and going to the bathroom is exhaust, veins are wires, hair is cosmetic, blinking is maintenance, toilets are waste disposal centers (technically, they already are tho), and lastly, the appendix was an error in the factory.