Scheduled air carriers

An airline is a company that provides air transport services for traveling passengers and freight. Airlines utilize aircraft to supply these services and may form partnerships or alliances with other airlines for codeshare agreements. Generally, airline companies are recognized with an air operating certificate or license issued by a governmental aviation body.

Airlines vary in size, from small domestic airlines to full-service international airlines. Airline services can be categorized as being intercontinental, domestic, regional, or international, and may be operated as scheduled services or charters. The largest airline currently is American Airlines Group.

DELAG, Deutsche Luftschiffahrts-Aktiengesellschaft was the world's first airline. It was founded on November 16, 1909 with government assistance, and operated airships manufactured by The Zeppelin Corporation. Its headquarters were in Frankfurt. The first fixed wing scheduled air service was started on January 1, 1914 from St. Petersburg, Florida to Tampa, Florida. The four oldest non-dirigible airlines that still exist are Netherlands' KLM (1919), Colombia's Avianca (1919), Australia's Qantas (1921), and the Czech Republic's Czech Airlines (1923).

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