Imagine that you are preparing a project with your friend. You have found some interesting material for the presentation and you want to read this text to your friend. You have 1.5 minutes to read the text silently, then be ready to read it out aloud. You will not have more than 1.5 minutes to read it. Atom consists of mostly nothing. The vast majority of an atom is empty space. To get it into perspective, imagine an atom the size of an international sports stadium. The electrons are right up at the top of the stands, each smaller than a pin-head. The nucleus of the atom is on the centre spot of the pitch, and is about the size of a pea. For many centuries, atoms, which were entirely theoretical, were thought to be the smallest possible units of matter, hence the word, which means not-cut in Greek. Then the electron was discovered. The atom was split and the neutron discovered in 1932. This was by no means the end of the matter. These even tinier units called quarks are given names like strangeness and charm and come not in different shapes and sizes but flavours. Whatever matter might be, no one seemed able to get to the bottom of it.