Recent Developments on Hadron Interaction and Dynamically Generated Resonances

In this talk I report on the recent developments in the subject of dynamically generated resonances. In particular I discuss the $\gamma p \to K^0 \Sigma^+$ and $\gamma n \to K^0 \Sigma^0$ reactions, with a peculiar behavior around the $K^{*0} \Lambda$ threshold, due to a $1/2^-$ resonance around 2035 MeV. Similarly, I discuss a BES experiment, $J/\psi \to \eta K^{*0} \bar K^{*0}$ decay, which provides evidence for a new $h_1$ resonance around 1830 MeV that was predicted from the vector-vector interaction. A short discussion is then made about recent advances in the charm and beauty sectors.