Imagine that you have gone back in time to the early 1800's, long before the dawn of technology. Now imagine trying to explain to them what a car is. What do you tell them? You could say that it has an engine and a place for people to sit, you could describe a steering wheel to them, and you could explain how it gets you places faster than walking would. You ask them to draw it back for you, and this is what you get:
Probably not quite what you had in mind, huh? Wouldn't it just have been easier to show them a picture of a car? The same goes for science, especially when it comes to atoms. Everything in science becomes so much easier when we can see how things work. But how is this possible when atoms are too small for us to see?