Current interest in ‘‘soft matter’’ has brought an old subject into new prominence. The soap froth, the prototype system for the coarsening behavior of cellular systems, is convenient for both theory and experiment, particularly in its two‐dimensional form. Following the lead of C. S. Smith in the 1950’s, painstaking experiments and extensive computer simulations of idealized models have confirmed his general conclusions and have revealed much else, including interesting transient behavior. The corresponding problem of metallurgical grain growth is also reviewed here.