Democritus - shiny, round, rough, or flat. It's all just atoms dude.

Democritus (460 BC - 370 BC) apparently is not the namesake for Democracy. The origin for that word is actually the Greek word "dēmokratía" which means "rule of the people".

What he is remembered for is his formulation of atomic theory. He wasn't thinking about what we think of as atoms though. At least, not exactly. Here is the popular conception of atoms:

Here is something more like the reality of what atoms actually are.

But he was really thinking of something more like oddly shaped building blocks or Legos.

For example, his theory is that water is made up of smooth round atoms. Rock consists of rough edged atoms that lock together. The color white was supposed to actually consist of smooth flat atoms while the human soul consisted of some other type of atom.

He also subscribed to a belief in a single god that he referred to as "cheerfulness". Everything about the world could be explained by atoms and the way they interacted. Remember that he was an ancient Greek and, popularly, the gods were quite numerous.

I tried to find a source which described all the different types of atoms that Democritus postulated, but it appears that most of his work was lost. Most of what we know about his theories comes from secondhand reports contrasting his views with the views of others.