Kohn–Sham equations are a set of equations used in physics to study how electrons interact with atoms to form molecules. Imagine that you have a bunch of balls, each ball represents an electron. The Kohn–Sham equations tell us how each of these electrons react with each other, which leads to the formation of molecules. In simpler terms, the Kohn–Sham equations help scientists figure out how different atoms come together to form molecules. It's like a map that tells us the best way for electrons to interact with each other so that atoms can form molecules.