Every adult these days has heard of atoms and maybe even protons and electrons. It's actually simple, protons (and neutrons) form the core of an atom and electrons float around this core on their orbits – or shells, if you want to be precise. So, there must be some space between the core and the electrons, which consists of – nothing. While this is hard for me to imagine, at least I'm not the only one having problems imagining this; on this website, someone has scaled a hydrogen-atom so that the electron has the size of 1 pixel, which makes the proton as big as 1000 pixels in diameter. But wait, here comes the impressive part: This means the radius of the scaled atom becomes 50 million pixels, that is 12.8 km on a 100ppi-screen!.
Visit the possibly widest website in the world to see an atom scaled so that its electron has the size of one pixel. http://www.phrenopolis.com/perspective/atom/index.html