This is an introductory lecture on some very basic principles of density functional theory, and some basic properties of density functional approximations. Useful references are "DFT in a nutshell", for beginners with any background, "A perspective on DFT" for a survey of the field a few years ago, and "The ABC of DFT", my long online unfinished textbook draft. All are available at http://dft.uci.edu.
The Cooper Union for the Advancement of Science and Art is pleased to provide support for the 2024 VWSCC through a generous donation from Alan Fortier.
We thank Leibniz Institute for Catalysis (LIKAT) and CECAM for their support.