Tiny molecules form all things around us – natural and man-made. In order to understand how these big objects we see behave on the large scale, we need a better understanding of what happens at the molecular level. Fortunately, we can come up with mathematical models that approximate microscopic behavior of, say, a water molecule, and use this to make predictions of properties of bigger things, like a block of ice. In this talk, we will together learn how to describe molecules using computers and a technique called molecular dynamics.