For example, appropriate for the days of festive excess, here is paracetamol (acetaminophen):
image from wikipedia.org
The red-coded regions of a molecule are most strongly pulled towards the blue-coded regions of others, while these regions push away regions that are similar to themselves; and thus the little molecules and atoms and ions move around and interact and react to make us what we are, we think.
Yes, they make us think.
And very fine and lovely they are too.