Bubbles and foams
Why studying foams? Because foams are everywhere. In food: chocolate mousse, bread, Chantilly cream. In cosmetics (shaving foam, shampoo) and in the kitchen (dishwashing liquid). Plastic and metal foams make matresses, sponges, bumpers.
Foams
are also used to separate ore by flotation in mines, or to extract oil. They're used for fire fighting as for industrial cleaning. They can even be a model system for other cellular materials, like for instance a tissue of biological cells. They're also related to other systems, such as granular media or complex networks. Finally they illustrate famous fundamental mathematical problems.