Hund metal physics: describing the normal state to understand the superconductivity of iron based superconductors

We will first review some anomalous properties of the normal state of the iron based superconductors. Then we will describe how we can understand them from the perspective of the theory of Hund metals, stressing the interesting many body physics that these materials in their paramagnetic phase. We will then present some phenomenology of the ordered phases and the extent that we can understand those features from the perspectives of the theory and conclude with challenges for future work.