OK so there are these tiny things called atoms, they make up molecules and we can see molecules with very powerful microscopes that ‘see’ by feeling. But how do we make stuff too small to see. There are many ways that scientists and engineers make things too small to see. And some of the ways are not new at all. Most computer chips are made using a process called photolithography. That is a big word but it sounds kind of like photography. Not digital photography but the old fashioned kind of photography where you use film. But unlike photography which has two dimensions, photolithography is three dimensional. Photolithography is a kind of lithography, which uses light (so the photo). The original process of lithography dates back over three-hundred years. Alois Senefelder (born with the gigantic name Aloys Johann Nepomuk Franz Senefelder) of Munich invented lithography, printing on stone, around 1798. That is over 100 years ago! He started off with the simple idea that oil and water do not mix. He figured out that you could write a pattern on something by first drawing with an oily substance (like a crayon). If you then smeared on a ink that was made up in water, it would only stick to places where there was no crayon marking. Alois would scribble over the whole surface with a crayon, then scratch away to ‘draw’ his pattern. Next he would coat the entire surface with ink where it would stick to only those places that he had scratched away the crayon. So what does that have to do with making computer chips?