Ryanair Holdings PLC, headquartered in Dublin, Ireland, is an ultra low-cost carrier group that includes subsidiaries such as Ryanair DAC, Malta Air, Buzz, Lauda Europe, and Ryanair UK, with its foundation dating back to 1984 and transitioning into a holding company format in 1996. The airline has experienced rapid expansion attributed to the deregulation of the European aviation industry and the adoption of a low-cost business model, operating over 500 aircraft and serving more than 40 countries across Europe, North Africa, and the Middle East. Despite its status as Ireland's largest airline and achieving the rank of the world’s largest airline by scheduled international passengers in 2016, Ryanair has faced criticism for practices related to VAT-exempt service invoicing, working conditions, additional charges, customer service, and controversial publicity strategies.