The document provides information on the history and development of commercial airlines globally. It discusses the founding and growth of early airlines in Europe, the United States, Asia and other regions. Some of the earliest airlines include DELAG (1909), KLM (1919), Avianca (1919) and Qantas (1921). The airline industry experienced rapid consolidation in the 1920s and growth in the 1950s with the introduction of jet aircraft. Key trends and largest airlines globally are also summarized.