In case you need your mind boggled today, here is something to feast upon. We all probably realize that the digital electronics that surrounds us in computers, phones, tablets and the like is extremely small. A lot of components are squeezed into a tiny, tiny area. The first digital computers like ENIAC (which were morons compared to a basic smartphone) would take up a large room, filled with vacuum tubes and wiring. Remember vacuum tubes (or "valves" to my UK friends)?
Over time, solid state electronics became refined and things got much, MUCH smaller. So much so, that a new manufacturing process just demonstrated by IBM has transistors at the 7nm size (that is seven nanometers to you and I). Considering a single human hair is around 100,000nm thick, then that is pretty darn small; mind-bogglingly small, actually. IBM expects to be able to fabricate up to 20 BILLION transistors on a single chip using that process.