"Asthma" derives from the Greek root alpha sigma theta mu alpha iota nu omega and means "gasping for breath". The term did not originally define a certain disease entity, but was used to describe the respiratory symptoms of a variety of lung diseases. Various models have been proposed over the centuries to understand the pathophysiological anomalies of asthma. At the beginning of the 20th century, asthma was seen as a unique disease characterized by "cramp-like conditions of the bronchial tubes". In line with the nature of asthma as a complex disease, the models for asthma pathogenesis have become more and more complex. Research has evolved from outdated ideas to a descriptive functional approach based on pathophysiology in cell and molecular biology, immunology, microbiology, and genetics/genomics.