Sure, you think the world is full of solid objects. You think the radio you're listening to is solid. You think the floor you're standing on or the chair you're sitting in is solid. Heck, you probably think that you yourself are a solid object. Wrong.
One of the strangest things modern atomic theory has shown us is that what we commonly take to be the world of solid objects is for the most part empty space. That's right. Even something as reliable as a table, a brick, a baseball, even your body, is by and large just empty space.
Why is that? It's because you, the baseball, and everything else is made up of atoms. And atoms themselves are mostly empty space... But wait! What about the protons and neutrons and stuff? Well, they're in there, but only in the very center. That's called the nucleus.
An atom's nucleus is surrounded by a cloud of orbiting electrons. Virtually all the mass of the atom -- the stuff and not the fluff -- is in the nucleus. And the nucleus is incredibly tiny compared to the overall size of the atom. In fact, it's about a hundred thousand times smaller. It's like a speck of dust floating around inside a cathedral. In between the dust speck and the cathedral walls is nothing but space.
So you are made up of things that are mostly empty space, with occasional specks floating in them. Does it make you feel kind of empty, too? Don't worry. Every other object in the world, from a pebble to Mount Everest, is the same way.