Abstract: Glassy materials are characterized by being solid (for all practical purpose) at low temperature in absence of a sharp transition from the liquid phase to the solid state.  They are ubiquitous in nature: among them, we find window glasses, wax, honey, mozzarella cheese... In spite of the very strong experimental and theoretical effort done in the last century, there are many questions that are opened.
During this seminar, I would also stress some progress that has been done in the recent years on hard spheres models of glasses.