Aviation is the practical aspect or art of aeronautics, being the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is a vital part of the increasingly globalized world economy, facilitating the growth of international trade, tourism and international investment, and connecting people across continents. The aviation industry itself is a major direct generator of employment and economic activity, in airline and airport operations, aircraft maintenance, air traffic management, head offices and activities directly serving air passengers, such as check-in, baggage handling, on-site retail and catering facilities. Direct impacts also include the activities of aerospace manufacturers selling aircraft and components to airlines and related businesses. The world’s airlines carry over 2.6 billion passengers a year and 48 million tones of freight. Providing these services generates 8.4 million direct jobs within the air transport industry and contributes $539 billion to global GDP. Compared with the GDP contribution of other sectors, the global air transport industry is larger than the pharmaceuticals ($445 billion), the textiles ($236 billion) or the automotive industries ($484 billion) and around half as big as the global chemicals ($977 billion) and food and beverage ($1,162 billion) sectors. Air transport also has important ‘multiplier’ effects, which mean that its overall contribution to global employment and GDP is much larger than its direct impact alone. These include employment and activities of suppliers to the air transport industry for example, aviation fuel suppliers; construction companies that build airport facilities; suppliers of sub-components used in aircraft; manufacturers of goods sold in airport retail outlets; and a wide variety of activities in the business services sector (such as call centers, information technology and accountancy). Over 9.3 million indirect jobs globally are supported through the purchase of goods and services by companies in the air transport industry. These indirect jobs contribute approximately $618 billion to global GDP.