The Kohn-Sham method is a computational approach used in density functional theory (DFT) to study the electronic structure of many-body systems, such as atoms and molecules. It simplifies complex interactions by introducing a set of non-interacting particles that have the same electron density as the real system. This allows for easier calculations while still capturing essential physical properties. In the Kohn-Sham framework, the total energy of a system is expressed as a functional of the electron density. The method involves solving a set of equations, known as the Kohn-Sham equations, which are derived from the principles of quantum mechanics. This approach is widely used in materials science and chemistry for predicting the behavior of various materials and chemical reactions.