In broad terms, the lifespan of foam involves the sequential stages of bubble formation, bubble coalescence, and eventual foam rupture. Foaming is essentially a delicate equilibrium between the pace of bubble formation and the rate of bubble/foam rupture. If the former is excessively sluggish or the latter is too rapid, foam may fail to materialize. These occurrences can be elucidated by considering timescales, allowing us to forecast the degree of foaming at various points on the Oh versus Re map, as illustrated in Figure .